Alleged trainers who authorities say played a key role in a 2009 al Qaeda plot to blow up packed New York subway cars were facing charges in Canada, police said Tuesday, although their whereabouts were unknown.

At a news conference in Winnipeg, Canadian police accused Ferid Imam, a former student at the University of Manitoba, of training Najibullah Zazi, the Afghanistan-born New Yorker who has pleaded guilty to trying to bomb the city’s subway system.

Imam was identified by the New York plotters as a weapons instructor who went by the name of “Youseff,” police said.
“This extensive and thorough national security investigation has provided us with the evidence we require to lay criminal charges,” said Bill Robinson, assistant commissioner with the Royal Canadian Mounted Police.

Imam, 30, is charged with instructing to carry out terrorist activity and conspiracy to participate in the activity of a terrorist group. Another Canadian, Miawand Yar, 27, was charged with conspiracy to participate in activity of a terrorist group and participation in the activity of terrorism. Yar is also a former student at the University of Manitoba.

Source: Paula Newton for CNN.