'An Absolute Disastrous Mess'

Updated 5/13/15, 11:34 a.m.

At a press conference on Wednesday morning, following the derailment on an Amtrak train near Philadelphia, Pennsylvania, on Tuesday night, officials announced the recovery of a black box, which investigators hope will shed some light on what might have cause the train to derail.

As medical teams continue to work the crash site, Philadelphia Mayor Michael Nutter noted not all passengers have been accounted for. He also added that Philadelphia hospitals had treated about 200 patients overnight and that half of them had been released.

"We are heartbroken by what we've experienced here," Nutter said. "We have not experienced anything like this in modern times."

An official from the National Transportation Safety Board also spoke on Wednesday morning and was bombarded by questions about the train’s speed along with concerns about the condition of the tracks. He urged patience and explained that an analysis of the black box would yield insights into how fast the train was going and what engineers did in the moments before the crash.

“You have a lot of questions, we have a lot of questions," NTSB official Robert Sumwalt told reporters. "We intend to answer many of those questions in the next 24 to 48 hours.”

At least six people are dead and dozens more are injured after an Amtrak train derailed in Philadelphia, Pennsylvania, on Tuesday night. The train, which had been traveling to New York from Washington, D.C., was carrying 238 passengers and five crew members at the time of the crash.