MONTREAL - The Hells Angels dumped hundreds of guns into the St. Lawrence River during the bloody 1990s war with the Rock Machine gang, says a federal study.

The report, based on information from informants, was obtained by QMI Agency and highlights the ease with which criminals bought and disposed of black-market weapons.

The Hells went to great lengths to cover their tracks amid a murder and bombing spree that targeted other bikers, prison guards and also killed bystanders.

The Jacques-Cartier bridge on the eastern edge of downtown Montreal was a favourite dumping ground for pistols and other black-market weapons the Hells had used to gun down rivals.

Three Hells Angels members agreed to speak with University of Montreal criminologists for the study commissioned by the Public Safety ministry.

One gangster said the Hells bought all of their guns on the black market and estimates he destroyed as many as 200 weapons.

"For all of the weapons we used ... the standing order was the following: use and destroy," the report quotes the biker as saying.

"Immediately after they were used, they ended up in the river."

He said he would discard a gun for any reason, even if it had been used to pistol-whip someone or for target shooting.

The bikers said their gun suppliers were based in the Kanesatake, Akwesasne and Kahnawake Mohawk communities in southern Quebec.

Bikers also bought unregistered guns on the Internet or under-the-table at gun shops.

The study concluded that police "simply do not have the necessary resources" to stop the flow of weapons.

A total of 165 people were killed in the biker war over control of lucrative Quebec drug territory between 1994 and 2002.

The death of a 10-year-old boy in a Montreal car bombing provoked public outrage that led to the gangsterism law and subsequent police raids that crippled biker gangs in Quebec.