In a press conference on Friday, the National Transportation Safety Board (NTSB) announced that they are investigating whether or not a projectile struck the Amtrak before it derailed in Port Richmond on Wednesday.

NTSB board member Robert Sumwalt explained the concerning cracked glass on front of Amtrak 188:

“We have seen damage to the left hand lower portion of the Amtrak windshield,” Sumwalt said. “We have asked the FBI to come in and look at [this] for us.”

This new development possibly connects Amtrak 188 with a separate incident on the same evening. At around 9:10 p.m., 20 minutes before the Amtrak crash, a SEPTA train traveling from Trenton to Philadelphia was struck with what SEPTA described as an "unknown projectile" close to where the Amtrak train derailed.

Sumwalt’s interview with engineers and conductors from both trains confirmed that they were both in communication about the unknown projectile. SEPTA engineers reportedly told Amtrak 188 that it has been “hit by a rock or shot at.”

Mayor Michael Nutter had said on Wednesday that the two incidents were unrelated.

Sumwalt also relayed his interview with the engineer of Amtrak 188, reporting that the engineer showed sound knowledge of the railways and their restrictions.

Earlier in the week, however, reports emerged that the Amtrak train may have been traveling over 100 mph at the time it derailed. The speed limit at Frankford junction where the train derailed is 50 mph.

On Friday, Temple University Hospital confirmed that five passengers were in critical condition.

Authorities have confirmed eight people died in the crash, with over 100 seriously injured.