A Vancouver man has been charged with stabbing another man in the face after the Sun Run on Sunday.

Calvin George Walker, 36, faces charges of assault with a weapon and possession of a weapon. He was arrested after he was chased down and held by race participants.

Witnesses told CTV News that they saw one man stab another just below the eye with a small knife in the 800-block of Carrall Street around 10:30 a.m.

The victim is a 36-year-old Surrey man. He was sent to hospital, where he was treated for a cut to his cheek and sinus injuries.

Vancouver Sun Run participant Antonio Cerullo said that he watched the stabbing and saw the suspect put the knife in his pocket and began running away.

"Wrong day to do something like that," Cerullo, who finished the Sun Run in just over 48 minutes, said. "There's 50,000 runners here, so unless you're a real runner you can't run away from us."

Cerullo said he was apprehensive about chasing an armed man, but was joined in the pursuit by about 10 others. It didn't take them long to catch up.

"A bunch of other runners, bigger guys, tackled him down here in the intersection," he said. "That was the end of his run."

Police arrived shortly after to find the runners waiting for them with a captive suspect.

On Sunday, Insp. Dean Robinson said that while the Good Samaritans helped police this time around, he doesn't generally encourage such attempts at heroism.

"We don't recommend chasing people that are armed," he said. "It worked out this time."

Robinson said the motivation for the attack was not clear, but it appeared "not much thought" had been put into it.