Friends of Ryan Dube, the 18-year-old who ran from police and leapt to his death in the Niagara Gorge this week, are still trying to piece together how a foot chase could end so tragically for a young man described as troubled but optimistic about his future.

Among those stunned to learn of Dube's death on Tuesday was Joshua Brooks, who lived with Dube at the Nightlight youth services group home in Niagara Falls.

Niagara Regional Police say a man being chased by a police officer leapt over a railing at River Road, between Eastwood and Otter Streets, and plunged to his death in the Niagara Gorge. (Google)

"I just saw his girlfriend crying," Brooks said. "And I didn't want to believe it."

Brooks speculated that a taxi-fare dispute may have led to the police pursuit, which also injured an officer who followed Dube and vaulted over a retaining wall near the Niagara Gorge.

"This police officer pulled him over and said he had a warrant for his arrest, and, like any other teenager, would run," Brooks said. "I was told yeah, it was because he ditched a cab."

Grief counsellors spoke with the youths on Wednesday to try to help them cope with the loss.

"Everybody's just trying to go see their friends, stay close," said Brianna Gearing, who also knew Dube.

Ontario's Special Investigations Unit said an officer was running after a teen just after 5 p.m. ET on Tuesday, along the edge of the Niagara Gorge and about three kilometres downstream from the falls.

Injured officer identified

The teen darted through a yard between Otter and Eastwood Streets before jumping over a retaining wall at River Road, witnesses said.

The drop is at least 30 metres.

"The kid went off the ledge, and the cop went with him," said Logan Tremblay, who was just steps away from the pair.

Niagara Regional Police Officer Const. Jacob Smits was rescued and airlifted to Hamilton Central Hospital, after suffering a broken femur (thigh bone). He underwent surgery on Wednesday.

JoAnne Turner, the executive director of the Boys and Girls Club of Niagara, said Dube was well-known and liked by staff at the Nightlight residence, and had been living there on and off since last year. She said in a statement that Dube was never known to be involved in any violent incidents.

Though Turner said Dube had occasional problems meeting curfew, the teen had apparently been trying to get his life in order and was looking for a job.

The province's Special Investigations Unit, which investigates police incidents involving death, serious injury or sexual assault, has assigned seven investigators and two forensic investigators to the case.