Doug LePard said the first shots were fired around 11 a.m. Tuesday outside a Starbucks in the city's Yaletown area, where a man was left fighting for his life on the pavement.
The mayhem was followed by a shootout between the suspect and two plain-clothes police officers who happened to be in the area to grab coffee.
LePard said the suspect fled on a bike along the city's seawall, with one of the officers commandeering a bike to follow him. Another exchange of gunfire erupted outside Science World, a popular tourist and family attraction.
He said dozens of officers flooded the area and found the suspect on the seawall near Science World.
"There were several exchanges of gunfire that occurred as the suspect was approaching Science World and officers were there setting up, waiting for him," LePard said.
"It is absolutely extraordinary. I've been a police officer for over 33 years. I've never seen anything like this happen in Vancouver."
Police have not named the victim, although an employee at a local bike shop confirmed it was the owner, Paul Dragan, who LePard said is in critical but stable condition in hospital.
LePard said the suspect, Gerald Battersby, was a former employee of the victim, who was shot once.
He said Battersby was shot numerous times by police outside Science World and among his injuries were wounds to his arm, leg and knee. Battersby is in hospital in serious condition, and under police guard.
LePard said a female officer who suffered significant injuries to her head from flying glass is doing fine and is otherwise unharmed. He said she was in a police cruiser when it was struck by gunfire.
LePard lauded several Good Samaritans, including a retired doctor, who helped the victim outside the coffee shop.
"No doubt he played an important role in that victim's survival so far," LePard said of Dr. Cliff Chase.
Chase, who worked as an emergency room doctor in Saskatchewan for 25 years, said he was leaving a store when his wife told him a man had been shot.
"You kick into procedure mode, you blank everything else out if you can, and you just do what you have to do," he said. "You're trained to intervene in whatever way you can."
Chase said the victim was lying on the ground unconscious, barely breathing, going into shock and bleeding heavily.
He said he lifted up the man's shirt but didn't see any blood on the front of his body so he turned him over and found he was bleeding from his back.
"When I did roll him over to see how much blood there was, and it was actively pumping out, I didn't see that there was one, or two or three shots," he said. "I just knew this fellow is not doing well. He was bleeding out very quickly."
Chase said he used a towel from the coffee shop to put pressure on a wound on the man's back and opened up his airways.
He said he didn't want to perform CPR because he wasn't sure how long it would take for the ambulance to arrive, and the victim would have bled even more had he used chest compressions.
Chase said he waited for the ambulance to arrive and take the victim to hospital, after which he finished his coffee and went home to eat lunch.
"So you know I didn't do a lot," he said.
Science World president Bryan Tisdall said between 400 and 500 visitors, including school children, were inside the building just before noon when gunfire erupted.
He said police asked Science World staff to lock down the building and that it remained locked for about three hours. Guests were told to stay away from doors and windows.
"Our objective was to maintain the sort of the comfort and enjoyment of visitors, and that's the point at which we, you know, offered free films, free popcorn, whatever we could do, because many of those folks had not anticipated that there stay may have been as long as it was going to be."
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