One man is dead and a police officer seriously injured after they plunged over a retaining wall near Niagara Falls Tuesday evening, in what appears to be a foot chase with a tragic ending.

Witnesses said that a police officer was chasing a male suspect around 5 p.m. when the suspect jumped over a retaining wall and into the Niagara Gorge, with the officer close behind him.

Niagara Police Const. Derek Watson estimated the drop was as much as 30 metres (100 feet), though he could not say exactly how far down the men fell.

The incident occurred on River Road, between Eastwood Street and Otter Street, about two kilometers north of Niagara Falls.

Niagara police, fire crews and park police confirmed the two men were located and both were alive when they were found, but suffering from serious injuries.

Video footage showed rescue crews were using a hard-framed basket attached to a fire truck boom to carry one emergency responder down to the victims.

According to CP24’s Cam Woolley, who is a former Ontario Provincial Police officer, crews had to move very slowly when using such a rescue device, to prevent the basket from swinging or spinning into the walls of the gorge.

The police officer was pulled out around 7:30 p.m., confirmed Niagara Police Const. Derek Watson.

The province’s Special Investigations Unit, which looks into serious incidents involving police, said that the officer had a broken leg.

The SIU confirmed that the second man died as a result of his injuries.

The SIU will now investigate the incident.