Surely you mean the meteorite impact?
NCC news:
Today a massive meteorite impact in Philadephia caused thousands of
deaths and ten thousands of causalites. Authorities believe that the
meteorite likely disintegrated shortly before impact explaining the
lack of remainders [possible!]. Soldiers from Fort XYZ [in reality
special ops] have already taken position to prevent looting until the
National Guard is able to send support.
Next news:
The authorities are informing the population that an illegal chemical
factory currently discovered in the ruins and destroyed by the impact
may be a severe security hazard. There are strong indications that
they bunkered a large amount of sulfuric acid. Sulfuric acid causes
severe burns on unprotected skin and can even cause blindness [it is
also an essential part of chemical laboratories and coincindentally a
cleansing agent]. For
this reason protected workers are now decontaminating the laboratory
which is very near to the meteorite impact [guess that noone near that
is alive?]. Please do not approach the ruins in a 2 mile radius until
the cleanup is completed.
Update with survivor interviews (both fakes):
Dirty, exhausted hobo with an alcohol bottle in his jacket:
I saw it! I saw it! A HUUUUUGE ALIEN saucer! It told me that it would
come! This is fulfilling the prophecy!
Nice, clean shaved businessman in suit, speaking normally:
Oh yes. A terrible tragedy! The day was suddenly
so bright! I could not look up and needed to shield my eyes with
my hands. And then it shook me and I was flying through the air! The
whole area was devastated and I could smell something terrible. I
just had to run and get out of the area immediately.
An expert speaks now, Professor Dr. XYZ which is the meteorite authority:
Well you know, it reminds me of the Chelyabinsk incident in Russia
where a meteorite exploded in mid-air and caused severe damage, but
fortunately very few casualties. It is rare, but not unheard of that
no smoke trail could be seen. First, it was night during the impact
and the impact caused a cloud of smoke rising which will cover the trail.
Second, even if that was not the case the meteor is likely
composed of denser material (rock or even iron) and when the atmosphere
get more and more dense on the ground, it puts more stress on the object
which finally causes disintegration without much ablation which is
necessary for a smoke trail. [Long, long essay about deepest
condolences and the dangers meteorites pose and how perfect the
evidence is].
Update:
The authorities inform us that several tons of rubble are blocking
the streets and impede the rescue progress. Also a large amount of
binding agent for the spilled chemicals must be transported. The army has
dispatched several heavy Boeing-Vertol CH-47 Chinook helicopters which
will be able to bring out both the rubble and the agent and save human
lives.
Taking on problems:
Being the first major meteorite strike with severe human losses in the
USA the authorities are surprised that the event seems to have caused
a mass hysteria. Some people insist against all common sense that the
meteorite strike was in fact an impact of an "alien spaceship" and
have posted grainy truther videos on Youtube. Psychologists have
already dubbed the new hysteria the "Philadephia syndrome".
Government speaker:
We are all at a loss to what happened! Unfortunately instead of
helping other people some individuals have now used the opportunity to
spread false rumors to gain attention. We do not know why they are
doing this, but be assured: If you believe to have gathered evidence,
inform the authorities about it and it will be evaluated neutrally and
with utmost scrunity. Luckily we have now real videos of the impact
[really, really billion-dollar good CGI]. I offer also my condolences
for the surviving families that the buildings of some of their
deceased family member has not only been destroyed by the impact but
the contents of the buildings has also been irrevocably destroyed by
the sulfuric acid. We know now that Mr Hastings [single, only distant
relatives] is responsible for storing the acid.
Phil Plait, skeptic and astronomer:
There have been many arguments during the years which makes the
implausibility of alien spacecraft obvious. The vast distances to
cover, the plausible reason to cover this distance, the lack of FTL
drives. And lets not forget, we astronomers look at the sky, if there
was no spacecraft there the whole time how good is the chance that
this is a real one?! I must admit that many posted videos are
extremely convincing, but given the equally valid counter-evidence we
must use Occams Razor. Extraordinary explanations need extraordinary
evidence. Unfortunately it is always the same: If we want to see the
originals, the people say that they are vanished [broken in] or
threatened by government officials with life-long prison. Do I need to
say more?
Some people do not understand when to give up...
The strongest zealot of the so-called "Philadelphia Truthers" has now
died by a tragic suicide. Malcolm McCoy, who was also known to believe
in the conspiracy theory of 9/11 and has a medicine record of a
depressive episode 25 years ago always declined the charges of Mrs.
XYZ who accused him of molesting her was found dead in his home. It seems
that he repeatedly stabbed himself in the back and bled to death.
Coroners who examined the body with utmost scrutiny said that suicide
was the only reasonable explanation.
Some time later (we need to have a good sleep):
We have gathered together to mourn the loss of the 17th regiment of
our Special Forces. They did their duty during the Philadelphia
meteorite strike and it is still unknown what exactly happened with the
transport plane.
For information: I am a role-playing gamemaster, and I use background mixed from reality with fiction. For example: What could be the real reason the Soviets used the Czar Bomb? Something terrific must be destroyed! I use then maps of the Novaya Zemlya, inform myself about the technology in the 1950s and prepare an invasion of a Great Old One which the player characters must fight. It spares me from having to invent everything, and it is also a nice history and geography lesson.
ADDITION: Some people believed it that it could not be suppressed for the reason everyone has now a smartphone, so someone would take pictures and send them over the net. Guess what, it is disturbingly easy to defeat. What I am talking about are IMSI-catchers which impersonates a mobile cell, can intercept any attempt to phone and is also able to locate the person immediately. So if you wandering into the zone with still a working ISMI-catcher your smartphone is worthless. Worse, the supervisors could immediately detect your presence in the area and find out your identify at once. So in effect the smartphone is a severe disadvantage.