By Tim Jimenez

PHILADELPHIA (CBS) — Amtrak’s CEO and federal safety officials will testify today at a Congressional hearing on the deadly derailment in Philadelphia thee weeks ago.

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Lawmakers are expected to pepper Amtrak CEO Joe Boardman and the Federal Railroad Administration’s Acting Administrator Sarah Feinberg with questions this morning.

One big question is why wasn’t a speed control system activated that would have slowed down Amtrak train 188, which was going 106 miles per hour at Frankford Junction?

In the crash three weeks ago, eight people were killed and 200 injured. The Northeast Corridor between Philadelphia and New York was shut down for a few days.

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After the crash, Amtrak activated a speed control system that had only been in place on one side of the tracks.

A major railroad union official is testifying as well. Their union, the BLET, after the crash, called for at least two people in the cabin. For decades, only one engineer in the locomotive has basically been standard procedure on the Northeast Corridor.

The NTSB is still investigating, and it could be a year before they release their findings on what exactly happened to cause the crash.

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As for the injured, the last update from Temple University Hospital says four patients are still there, two in critical condition.