Delta police and the BC Coroners Service are investigating a fatal collision involving a train on Saturday afternoon.

Authorities said it happened around 3:20 p.m. at the 4600-block of 72 Street near Ladner Trunk Road.

Mark Teasdale was in the area when he noticed the chaos.

"We saw the hood of the semi on one side of the track and it looked like something on the other side of the track," he said.

The crash involved a CN freight train and a Smithrite disposal truck.

Teasdale said another driver crossed the track to try to rescue the dumpster truck driver who appeared to be trapped.

CN officials have been called to assist police with the investigation.

"The crossing is equipped with active warning devices which were working at the time of the incident," said Jonathan Abecassis, a CN spokesperson.

"Our thoughts are with the person affected by this incident and their families."

The victim's identity has not been released.