PHILADELPHIA (CBS) — The National Transportation Safety Board has issued a preliminary report on last month’s Norristown High-Speed Line crash at 69th Street.

Slippery rails and speed warnings are in the NTSB’s preliminary report into the August 22nd crash.

NTSB Investigating After 33 Injured When Train Crashes At 69th Street Terminal

Thirty two passengers and the train operator were injured when the Norristown High Speed Line train crashed into an empty rail car at the 69th Street Transportation Center.

The NTSB says the operator told investigators he’d made eight runs on the line without incident that night. But on the final run in a light rain he said the train slid past the Gulph Mills station because of slippery rails.

Then, as the train approached 69th Street, an Automatic Train Control system alerted the operator to slow down.

The operator said he applied the brakes, but the train went past a stop signal and rammed into the unoccupied car.

The report did not determine a probable cause — that’s months away.

SEPTA declined to comment on the report.