The Amtrak engineer at the controls of the engine that slammed into a stopped Long Island Rail Road train was suspended without pay as officials blamed him yesterday for the accident.

The engineer either failed to hit his brakes or braked too late to avoid crashing into the back of the packed LIRR train in a Manhattan tunnel leading to Penn Station on Monday morning, officials said. A joint investigation by Amtrak and the LIRR found human error - not mechanical problems - caused the crash, Amtrak spokesman Dan Stessel said.

None of the 127 injuries was life-threatening. Most involved bruises, cuts and back and neck pain. But it was a traumatic experience for many riders who initially thought the train was attacked by terrorists.

"The person should have been more careful," said commuter Kingsley Gyamfi, 38, of Holbrook, L.I. "Anyone can make an error, but when you are driving a train in a tunnel you have to be more careful than the average person. It would be good if he would apologize."

Gyamfi was enduring back, neck and chest pains yesterday.

Amtrak would not release the engineer's name or work record. The investigation is ongoing.

Drug and alcohol test results were not available yesterday. Investigators who interviewed the engineer Monday did not suspect he was under the influence of either, a source said.

Trackside signals were set to alert the Amtrak crew that a train was ahead and to be prepared to stop if necessary, officials said, and the Amtrak train was going less than 15 mph, as required.

The LIRR train was stopped at a signal awaiting clearance to continue to a Penn Station platform when it was struck. The engineer could be fired, depending on the outcome of a formal internal hearing, Stessel said.