The Rock Machine biker gang - sworn enemy of the Hells Angels - is back in Montreal after a 10-year absence.

About 10 people proudly displaying Rock Machine colours were spotted in a downtown Montreal strip club on Thursday and were questioned by police, confirmed Danny Richer of the Montreal police.

After answering questions from officers, the individuals left quietly.

Police said that Rock Machine members showing off in Hells territory is provocative.

A client of the strip club who wanted to remain anonymous said that the bikers wore Rock Machine vests emblazoned with the word "Canada" as well as "1%" - symbols of the biker gang.

Their presence gives credence to the theory that the Hells Angels gang in Quebec has been weakened after 130 of its members and supporters were arrested in April 2009.

The Hells and the Rock Machine fought a bloody war between 1994 and 2002 that killed 160 people.

The gang was virtually wiped out of Quebec after the war and after several members defected when the group became a chapter of the American Bandidos biker gang in 2001. The Rock Machine restarted after the Bandidos broke up in 2006.

QMI Agency has learned that Rock Machine members have been spotted across the city in the past few months.

The Rock Machine gang has been causing problems recently in other Canadian cities, most notably in Winnipeg, where gun fights and arsons have occurred between them and another gang affiliated with the Hells.

Important events tied to the Rock Machine in Quebec

1985: The Rock Machine is started by brothers Salvatore and Giovanni Cazzetta.

1994: Start of war against the Hells Angels.

2000: Announcement of short-lived truce between Hells and Rock Machine.

2001: The Rock Machine officially becomes a chapter of the American biker gang, the Bandidos.

2002: End of war against Hells Angels. 160 people killed since 1994.

2003: Former head office of Rock Machine in Montreal is demolished.