A deadly shooting outside a Hells Angels-affiliated biker hangout in east London could fuel even more gang violence, a leading biker expert warns.

Police arrested five people after Steve Sinclair, 49, was gunned down outside a social club in a plaza on Hamilton Road at Gore Road, but have since said none of them was involved in the early-morning Sunday shooting, the city’s sixth homicide of the year.

Sinclair had leased space in the single-storey building to operate a club frequented by members of the Gate Keepers, a support club for the Hells Angels that has chapters in Perth, Elgin and Middlesex counties. He was a member of the Gate Keepers, sources say.

Yves Lavigne, the author of several books on the Hells Angels, said the weekend shooting likely was meant to send a message to the biker gang and its supporters.

“There will be more violence,” he predicted, suggesting the Hells Angels will have no choice but to respond to the shooting, or risk losing turf in London, if the slaying was aimed at them.

“If they (Hells Angels) don’t back that support gang, they lose face,” he said Monday.

“No one will work for them if they don’t back up their workers.”

But another source with connections to area bikers, who did not want to be named, said the shooting could have been an inside job, triggered by an internal dispute between the Hells Angels and Sinclair or the Gate Keepers.

The Hells Angels have kept a low profile in London since an outburst of violence and arson in January 2012, during what police then said was a turf war with rival street gangs over the city’s illegal drug trade. Five businesses, some with biker connections, were torched and two people, one of them a full-patch member of the Hells Angels, were shot.

Police wouldn’t comment on a motive for Sinclair’s killing, including whether it was biker- or gang-related.

Investigators hadn’t retrieved a weapon and were still holding the scene Monday.

Police were looking for a suspect described as a slim black man, between 18 and 22 years old and between five-foot-eight and five-foot-eleven tall.

Sinclair was a sheet metal worker by trade, with ties to outlaw motorcycle clubs.

Monday night, in a dramatic show of support for Sinclair, bikers on more than 100 machines gathered outside the Vancouver Street home where he lived with his family and rumbled off in a memorial ride. Supporters included men wearing colours and patches of several clubs, including the Hells Angels and the Gate Keepers. Cars filled with people also joined in the ride, which went past the shooting scene where police officers watched.

Friends and family took to Facebook this weekend to mourn Sinclair’s death.

His teenage daughter Sierra posted a tribute to her dad, calling him “my rock, my teacher, my friend . . . my world.”

“He always did what he wanted to do. If he wanted GREEN NIKE SANDALS, he would get them and still look like a true boss,” she said in her post. “I lost a real hero today.”

Others posted a message, “In memory of fallen bikers,” along with images of Sinclair.

Members of both the Hells Angels and the Gate Keepers were seen cruising by the crime scene just hours after the shooting. Two motorcycle-riding men, one wearing a Hells Angels vest, drove past slowly the taped-off plaza. About 15 minutes later, another motorcyclist in a Gate Keepers vest cruised by, with a woman on the back wiping away tears.

Police responded to reports of a shooting at the plaza shortly after 5 a.m. Sunday. Sinclair was in critical condition when paramedics took him to hospital, where he was pronounced dead.

Neighbours say the private club is often the scene of wild weekend parties that sometimes turn violent.

The only sign on the nondescript club is a warning that the building has a security system. The windows are reinforced with steel bars and a black tarp shields the outdoor patio area from sight.

“I’ve seen a lot of vests going in,” said one neighbour, referring to leather vests worn by bikers.

Hamdi Ebied, the plaza owner, says he leased a commercial space to Sinclair for the past two years to operate a “social club.”

Sinclair often applied for liquor licences for weekend parties, said Ebied, who called him a good tenant.

“He paid his rent,” said Ebied, adding he had no knowledge of any biker connections to the club.

Two weeks ago London rockers Bobnoxious played at the club for an event billed as “Steve’s 10th annual BBQ.”

Bobnoxious frontman Bob Reid had been a close friend of Sinclair since the two were teenagers, when Sinclair played bass for London band Dyoxen.

“I’m devastated, I’m stunned. He was a very good friend of mine,” said Reid, who was joined onstage by Sinclair at the Aug. 22 bash.

“He was happy to jump up there. It was his party,” said Reid.

When asked about the club’s biker affiliation, Reid said, “I don’t know, I don’t want to go there.”

With files by Randy Richmond and Jane Sims, Free Press reporters

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