PORT JEFFERSON, N.Y. (AP) — A government official says an engineer noticed a significant bend in a rail ahead and hit the emergency brakes before a passenger train derailed in western Kansas.

The U.S. official who was briefed on the investigation into the early Monday derailment of the Amtrak train says the train appears to have been travelling at about 75 miles when the engineer pulled the emergency break, slowing the train.

The official spoke to The Associated Press on the condition of anonymity because the official wasn’t authorized to speak publicly about the ongoing federal probe.

Amtrak says 32 people were taken to hospitals for treatment and that 29 had been released by late morning. The train was travelling from Los Angeles to Chicago.