(CNN) – Investigators with the National Transportation Safety Board are working to find out if mechanical failure or human error was to blame for this week’s deadly train derailment in Philadelphia.
U.S. Navy shipman Justin Zemser is the first of eight crash victims to be laid to rest. As his family bids a final farewell Friday, the investigation into what caused the deadly derailment will likely carry on into the weekend.
Investigators removed one of coaches from the crash site; the mangled metal, covered with a black tarp.
Some of the focus remains on Brandon Bostian, the engineer of train number 188.
The NTSB says it has obtained video showing the moments before the crash. The train seems to accelerate from less than 70 miles an hour to 106 in only 65 seconds.
Investigators are hopeful Bostian, who has suffered a concussion, can help them learn why that happened.
“We’re very excited that he’s agreed to talk to us. We plan to do it in the next few days.”
Investigators are left to pour over the rest of the evidence until that interview happens.
The derailment disaster is renewing debate over federal spending on the nation’s aging rail infrastructure.
“We cannot continue to make excuses for relying on our outdated rail infrastructure.”
Amtrak continues working to install an automated speed control system throughout its entire north-east corridor. Known as positive train control, the system could have overridden human errors and slowed the train down had it been in place where the derailment happened.
State prosecutors are now involved and are determining whether there is sufficient evidence to purse any criminal charges against the train’s engineer, Brandon Bostian.
An official close to the investigation says Bostian met with NTSB investigators Friday afternoon.
According to an official with the Philadelphia District Attorney’s Office, they are is closely monitoring the police investigation and awaiting results from NTSB’s accident investigation.
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