Sgt. Randy Fincham says just before 10 p.m. Friday witnesses called police after they found a body in Andy Livingstone Park near Expo Boulevard and Carrall Street.
The VPD's volunteer Citizens' Crime Watch saw a suspicious man running from the park minutes later and notified their police co-ordinator who detained the suspect.
Police say the suspect is 26-year-old Matthew Brenner of Vancouver and he has been charged with second-degree murder and remains in custody.
Fincham says police are still notifying family of the deceased man, a 44-year-old who had recently arrived in the city.
Homicide investigators and the VPD's Forensic Identification Unit were on the scene Friday night and well into Saturday.
"If it wasn't for the dedication and quick thinking of the volunteers in the VPD's Citizens' Crime Watch, we would not have been able to take this dangerous offender off the street so quickly," says Fincham in a statement.