Federal safety regulators and Amtrak officials face questions at a congressional hearing Tuesday on why technology to slow trains that are going too fast wasn’t in place before last month’s deadly derailment in Philadelphia.

The hearing by the House transportation committee comes amid rising concern about rail safety. There have been seven major passenger and freight train accidents this year.

Accident investigators have said Amtrak’s train 188 was going 106 miles per hour just before it derailed on a curve with a 50 mph speed limit. Eight passengers were killed and about 200 were injured.

Amtrak has long had technology called automatic train control on some tracks leading up to curves along its 450-plus mile Northeast Corridor from Boston to Washington, but not on the tracks before the Philadelphia curve.

(AP)