NEWTON, Mass. (AP) – The MBTA trolley that crashed into the rear of another trolley in Newton earlier this week, killing the operator and injuring a dozen passengers, was going nearly 30 mph faster than it should have been, a federal investigator said Saturday.

Tests on the signal system Saturday determined that the train’s operator encountered a red signal at the Waban station, which requires a 60-second stop, said Kitty Higgins of the National Transportation Safety Board.

Following the mandatory stop, operators are allowed to proceed at no more than 10 mph.

But the trolley operated by Terrese Edmonds was going 37 to 38 mph when it struck the rear of the other train, which was going 3 to 4 mph, Higgins said.

“The train left the Waban station at a speed higher than authorized,” she said. “What we don’t know is why that happened.”

Edmonds, 24, died in Wednesday’s crash at the height of rush hour on the D branch of the Green Line just outside the Woodlands station in suburban Newton. An estimated 200 passengers were on the two trolleys at the time.

NTSB investigators are continuing to look into reports from passengers that Edmonds was using a cell phone in the moments before the crash, Higgins said. Massachusetts Bay Transportation Authority train operators are expressly prohibited from using cell phones on the job, she said.

Investigators also got results Saturday of drug and alcohol tests on the other three MBTA employees on the trains at the time of the crash. They were all negative. Toxicology tests are also being performed on Edmonds, but those results are not expected for some time, she said.

Track and brake problems have previously been ruled out as the cause of the crash.

The NTSB is planning to do a so-called “sight distance” reconstruction test on Sunday at about the same time as Wednesday’s accident to help them determine what the train operator saw before the accident, and whether her view was obstructed.

AP-ES-05-31-08 1528EDT

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