There is a lengthy background to this, which I feel is relevant. Yes, the title is supposed to be somewhat B-movie-esque.
For some reason, there are Sasquatch-vampires (more on their biology later) on this version of Earth in addition to humans; they have been here since well before humanity left Africa, evolved in such a similar fashion that they were sentient (as we define a human as sentient) at essentially the same time, have integrated themselves into society in all aspects, and live world-wide. Asking how they got here is irrelevant to this question. Were they an alien tool for exterminating humanity that went rogue? Were they sent back in time by future humans for entertainment? Did they evolve naturally? Were they spun into existence by an Internet sci-fi writer? Those questions don't matter for the purposes of this one - they are here, here they are.
A certain group of Sasquatch-vampires were originally concentrated around an area that happened to have a technologically-advanced alien artifact in it. Advances derived from said artifact in their rough equivalent of the 1600s - simple things by our standards, such as "electricity", "vaccines", and "modern fertilizers", as well as a draconian government attempt at keeping the secrets behind the stuff under wraps - helped the local Sasquatch-vampire population and their human allies take over a land empire roughly comparable to the Roman Empire at its height, as well as Scotland/Ireland and a larger portion of Central/Northern Europe.
However, said empire "maxed out" at approximately that size, and, despite the overall situation remaining relatively stable, its leaders realized that they were overextending, and that, despite their (shrinking) technological advantage, there were simply too many forces allied against them in order for them to hold all of their land.
Therefore, over the course of the next few hundred years, said empire slowly shrunk and retreated into its core territories over time until it merely took up the Iberian Peninsula, submitting to various military disarmament and territorial dismemberment treaties along the way in exchange for guarantees of sovereignty. In their equivalent of the 2020s, new leadership (somewhat similar to Nazis, but with several notable differences) took over in a xenophobic, anti-human, pro-vampire military coup, immediately after which said state, despite being small and relatively weak at this point, became the first nation in the world to crack the code on nuclear technology due to their extraterrestrial technological edge (there's been a bit of a stifling of nuclear technology in this world due to a relative lack of warfare compared to ours).
Nationalistic and expansionistic sentiment, derived in part from the old Sasquatch-vampire empire, flared - "we have nukes, they don't" mingled with "they're on our land" mingled with "humans are food/an inferior form of sentient life" - meaning that, unlike the nuclear-armed United States after World War 2, this country was very interested in expanding its borders. They subsequently invade their "human-contaminated" neighbors, systemically nuking the tobacco juice out of them along the way and leaving behind a trail of devastated cropland, shattered infrastructure, and radioactive fallout. They expand to territory equivalent to their old empire, as well as the equivalent of Nazi Germany's expansion into Europe.
A few years into this, there's an ideological dispute ("should we simply reclaim the old empire, or should we try to take over ze world?"). A few years after that, the Glorious Leader/head honcho/center of the cult of personality/leadership figure is assassinated over it. All the generals who are leading this hyper-militaristic expansion effort decide to go their own way (long story short, there's a set of socioeconomic circumstances that allows them to do this without running out of supplies or personnel in the medium-term), resulting in warlordism that quickly devolves into a regional nuclear war with late-1940s/early-1950s-style gun-type and boosted fission weapons with yields in the hundreds of kilotons at most.
Essentially, every population center, military facility, shipyard, strategic command center, or other semi-important node in this graphic, as well as a good chunk of North Africa, gets hit with an A-bomb.
Now (and only now), we get to more relevant context.
This particular part of a story I'm writing involves a group of human survivors attempting to hold out against remnants of the Sasquatch-vampire military that are operating in the region post-nuclear-apocalypse.
A Sasquatch-vampire is a rather formidable entity, whose physical characteristics I will list all of in case one is relevant to the question:
they vary from six to twelve feet tall, and 85 to 470 kilograms/187 to 1036 pounds
they are covered in a layer of thick, wooly hair similar to that of a llama
they are as intelligent as a human being, albeit these particular ones are rather unpleasant ones
although nocturnal, they are not injured by, damaged by, or averse to light
there is nothing supernatural about them
all individuals have a tapetum lucidum, enabling them to see in low-light conditions
they need to ingest approximately a teaspoon of human blood per day for its T-cell content (it has to be human blood, long story), but they get narcotic highs the more they ingest; moreover, these particular individuals would rather take it all for social/personal/mental/ideological reasons
they feed on blood via scraping skin off of the neck or wrist lion-style and lapping up the resultant blood; unsurprisingly, this is highly uncomfortable for unwilling humans on various levels
other than the blood, they eat "normal" (as defined by a human) foods, albeit in significantly greater quantities than a human
they are capable of regenerating trauma notably faster than a human (i.e. within days rather than weeks), although they can't do things like "regrowing limbs" or "fixing organs" - they die to the same things humans do, just on a larger scale
they have a lot more neural activation than humans, meaning that they're proportionately stronger (I'd put it as "most of them can bench-press a motorcycle"), since they can "use more muscle per muscle"; the microtears/abrasions in their muscle tissues that are a result of this aren't really a problem due to their heightened regenerative ability
they have a spring-loaded joint in their legs that enables them to vertically jump approximately three feet from a standstill without training
they can climb walls gecko-style; yes, this is scientifically possible even if they weigh half a ton
they are burst/ambush predators, and (unencumbered) can run at speeds comparable to/faster than Usain Bolt for a few minutes
they have airbag-like sacs between their ribs to reduce damage due to blunt-force trauma
they have bones that are a mix of bone and nacre; meaning that they can take significantly more compressive force relative to their size in comparison to "normal" life
their skin is bullet-resistant, if certainly not bulletproof
while they can speak in human tones, they can also communicate in infrasound wavelengths between 20 and 0.1 Hertz
they are warmblooded and appear on IR scanners
their hearing and vision are probably describable as "peak-human", and their sense of smell is more like a dog's
their joint fibers are made of resilin, enabling them to survive higher falls and forces with less damage than a human would withstand
they can carry heavier body armor and weapons than humans; for instance, your average Sasquatch-vampire soldier might be lugging around multiple layers of Kevlar, a SCAR-H 7.62mm rifle, or a Squad Automatic Weapon plus the ammunition required; crew-served weapons are something along the lines of 50-caliber machine guns or 20-millimeter anti-material rifles
The human characters are baseline humans as we would know them. They are an undersized (i.e. ~75% their normal number) company-strength force similar to a modern US Army infantry company, without armor, artillery (beyond what's already organically embedded in their company; i.e. mortars), or air support who are attempting to defend a massive military supply storage, processing, and handling complex (such massive stockpiles of undamaged supplies - everything from munitions to food to spare parts - are part of the reason the warlord states aren't collapsing) that was built during the atomic crusade/murderfest westward by the Sasquatch-vampires, and which was too small to allocate a nuke to (approximately rectangular, 1500 meters to a side, with some buildings that are three stories tall, and in a relatively rural/isolated area) from roving bands of Sasquatch-vampires who are attempting to infiltrate it. There are about 500 human civilians in the place.
Sasquatch-vampire attacks are anything from a lone drifter/deserter (i.e. one individual armed with the weapons outlined above) up to a company-level force (also with the weapons outlined above, meaning no air support, no armor, and only the artillery they have with them), and anything in between; it might be one of them one week and a hundred the next. Other than the obvious physical differences and differences in armament, it's also useful to note that their organizational structure has mostly broken down: they are no longer military units, but bandits (albeit very well-trained ones).
There is one Sasquatch-vampire attack/attempt to get in a week, on average. It varies in magnitude.
The Sasquatch-vampires essentially possess the fanatic mentality of a top-notch SS unit, due to their adherence to one side of that ideological debate I mentioned (i.e. "humans are food/slaves, not people"); all the sane/non-mass-murderey ones are staying well away from this facility. The ones doing the attacking are not afraid of the humans and cannot be "bought" with donations of blood; they want to destroy the people resisting them, enslave the rest, and turn the facility into a hideout. Period. Done.
They're also not going to go away, because the humans at the facility are the only source of human blood in a wide radius, since most of the others are dead. Moreover, if two separate groups arrive, they'll probably ally with one another; the humans are the common enemy. They aren't a coordinated, organized force, they're a bunch of well-armed, well-trained bandits.
Supplies are essentially not a concern for the humans, given that they're in a military storage facility chock-full of them.
Said facility has a series of bomb-proof (i.e. anti-nuclear) personnel shelters that can fit every human on the premises, but next to none of the supplies. It also has a series of ammo bunkers to protect against shelling, meaning that the Sasquatch-vampires can't set off the human ammo supply via mortar. However, both are vulnerable to getting smoked out by foot infantry.
Food is not a concern for the Sasquatch-vampires for a few weeks after they arrive. Blood is not a problem ever because they need a mere teaspoon a day, and they probably caught and drained some band of roaming civilians a bit back - or brought them along as constantly-regenerating juiceboxes.
Them getting in long enough to shoot civilians/blow up supply storage facilities counts as a failure on the part of the humans, and it doesn't have to be a direct attack - they might just try infiltrating. Mortar/artillery/lobbed grenade attacks do not count due to the aforementioned personnel shelters and ammo bunkers; their win condition is "dig the humans out".
The humans holding out long enough for humanitarian (so to speak) aid and a subsequent peacekeeping force to get to them is their win condition; I'm presuming it would take ~half a year, despite the fact that essentially everything in the world was mobilized to support disaster relief after the nuclear war.
"Retreat and blow the stuff up" is not an option for the humans, because this is in a post-nuclear wasteland, and it's the only cache of food/munitions for a while around, as well as the fortified position - sure, they could leave, but there's no "better position" to retreat to, and they can only take so much with them.
Given all of that, here's my question:
Given the superhuman physical attributes and general fanaticism of the Sasquatch-vampires, what tactics, strategies, or methods of combat and/or organization can the humans (both military and civilian; although the civilians are unarmed and not trained military-wise, they have access to a wide variety of infantry weapons) in this facility use in order to stop roving bands of them from getting inside and to kill them?
Specifically, I'm looking for answers that take into account that the Sasquatch-vampires can subvert a lot of methods of keeping them out:
Walls? They climb them.
They'll probably win one-on-one with a human in any kind of fight, including a gunfight and especially in hand-to-hand combat.
Chain link with barbed wire? They can pull it down.
Shot to the torso? Won't put the bigger ones out of action for long, and unless they hit the heart it won't kill them instantly either.
20-foot drop in full gear? Non-problem.
They can outrun most humans in the facility long enough to catch them.
IR scanners to detect infiltrators? They can wait for some of Europe's nastiest weather to get in their way.
They can always attack at night if they so choose - i.e. when humans are most vulnerable.
Now, I recognize that you might say "normal tactics usable against humans would work on them too", but if Olympic-level physical capabilities, double-layered body armor, bullet-resistant skin, general physical durability, natural night vision, a capability for healing flesh wounds in days, the ability to hang upside-down from ceilings, and the grab bag of other fun stuff doesn't change how people deal with these things, I'd be very surprised.