Chicago ? A commuter train was going almost 60 mph above the speed limit just before it derailed, killing two people and injuring dozens of others, the acting chairman of the National Transportation Safety Board said Sunday.

Mark Rosenker said the Metra train was traveling at 69 mph and should not have been going faster than 10 mph when it switched tracks at a crossover just before jumping the tracks Saturday.

“Sixty-nine miles an hour is very, very fast when you’re dealing with a 10-mile-an-hour restriction,” Rosenker said.

The speed information came from a preliminary reading of one of the train’s three electronic data recorders, popularly known as “black boxes,” Rosenker said.

Investigators conducted a three-hour interview Sunday with the train’s engineer. The 41-year-old man had been on the job for 45 days after completing Metra’s six-month training program, which included at least some training along the route where the derailment occurred. He also had worked for more than five years as a CSX Corp. freight train engineer.

Chicago firefighters carry an injured passenger to an ambulance after a train derailed, killing two passengers and injuring more than 80 others, Saturday in Chicago.

The double-decker commuter train was headed into Chicago from Joliet on Saturday morning with 185 passengers and four crew members when its locomotive and five rail cars jumped the tracks about 5 miles south of downtown.

The train and the track had just been inspected Friday, said Judy Pardonnet, a spokeswoman for Metra, the commuter rail system that services the Chicago area.

Transportation officials also determined Sunday that train signals were working, meaning the engineer should have known he was approaching a crossover and should have had time to slow the train upon seeing the signals, even if he was traveling 69 mph, Rosenker said.