The five-hour standoff in the Starlight Casino parking lot snarled traffic for hours throughout the Lower Mainland as New Westminster police tried to negotiate with the unidentified man.
He has not been charged.
Initially, 911 calls were made for "shots fired" just before 6 a.m., and police went to the scene, according to the Independent Investigations Office that has taken over the file.
Witnesses reported hearing a loud bang at 10:45 a.m., as police were negotiating.
"An officer-involved shooting occurred and, as a result, the male sustained serious injuries and was transported to hospital," Kellie Kilpatrick, spokeswoman for the investigations office, said in a statement.
Police said there was never any immediate danger to the public. The casino was locked down, with patrons and employees kept inside, according to Insp. Phil Eastwood.
"The call involved the fact that there was a male outside the casino in the car park with what was assumed to be at that time a handgun. He was with a female," he said.
"The female with him was able to move away from the individual and she is now safe with the New Westminster Police Department."
Police confirmed there was a relationship between the two.
- With files from Ada Slivinski