OLD ORCHARD BEACH — One of Amtrak’s Downeaster passenger trains struck and killed a man shortly before 3 p.m. Tuesday, Old Orchard Beach police have confirmed.

Lt. Timothy DeLuca said that a white male was killed when he stepped out in front of the southbound train at the Union Avenue Crossing. The man was pronounced dead at the scene.

Police were still working to identify the man as of early Tuesday evening, DeLuca said. Once his name has been confirmed and his family has been notified, police will release his identity, he said.

DeLuca said several witnesses told police that the man who was killed was awaiting the train’s arrival when he “walked directly into the path of the train upon its approach to the Union Avenue crossing” in what appeared to be a suicide.

DeLuca said the incident remains under investigation by the Old Orchard Police Department, with assistance from the Amtrak Police and the Boston and Maine Railroad Police. Additional witness statements and evidence are being gathered, he said.

The rail service announced late Tuesday afternoon that its train 686 was involved in an “incident” in Old Orchard Beach that would delay the train. The nature of the incident was not disclosed.

Just after 5 p.m., Amtrak posted on its Downeaster website that the 686 train was “back on the move,” running one hour and 45 minutes behind schedule. The subsequent 687 train also was expected to be delayed by about two hours because of the incident, according to Amtrak.