Counterterrorism officials on both sides of the border announced charges against a 30-year-old Canadian fugitive Tuesday, going public with their long-held suspicions that he trained al-Qaeda operatives who tried to kill U.S. citizens.
Ferid Imam, once a biochemistry student at the University of Manitoba, faces the equivalent of two life sentences - one in Canada, one in the U.S. - should he ever be caught and convicted. He is wanted in connection with a 2009 scheme to bomb the New York subway system.
There is no allegation Mr. Imam was directly involved in the thwarted attack. Rather, he stands accused of being a training-camp instructor in Pakistan's tribal regions, a man who schooled other "homegrown" radicals later caught in the United States.
The three suspects apprehended in that scheme were New Yorkers. Two of them have since admitted their crimes, telling police they had trained with al-Qaeda figures who had tasked them with becoming suicide bombers.
"Ferid Imam helped them get that training," Janice Fedarcyk of the U.S. Federal Bureau of Investigation said in a statement. "Today's charges are an important step in bringing to justice all the conspirators."
As prosecutors in Brooklyn named Mr. Imam in a new indictment, Canadian police in Winnipeg obtained arrest warrants on related charges.
At a news conference, the RCMP revealed that one of the New York subway bombers has fingered Mr. Imam as being a training-camp instructor in Waziristan, Pakistan.
Such evidence has given Canadian authorities confidence to pursue their own criminal case alleging that Mr. Imam is a terrorist instructor - the first planned Canadian prosecution for terrorist crimes alleged to have taken place entirely overseas.
For any trial to happen, authorities would first have to arrest Mr. Imam, who is elusive. He has been the subject of a global hunt for years.
After immigrating to Canada from East Africa at age 7, he was a popular high-school student. Mr. Imam gravitated toward fundamentalism in his 20s as he studied at the University of Manitoba.
In 2007, Canadian police were alarmed to learn from Manitoba Muslims that some students were disappearing to places unknown. The first tip came when the family of Miawand Yar, a mechanical engineering student who is now 27, called to report him missing.
The RCMP said Tuesday that Mr. Yar and Mr. Imam were photographed upon their arrival in Karachi, Pakistan, in 2007, before they moved on to the border town of Peshawar.
Assistant RCMP Commissioner Bill Robinson told reporters that the two men had spoken of going to Afghanistan to join the Taliban, though there is no information indicating they ever left Pakistan.
On Monday, the Mounties got warrants alleging Mr. Imam is a terrorist trainer and alleging that his accomplice, Mr. Yar, is guilty of the lesser charge of participating in terrorist activity.
The U.S. charge sheets suggest other connections.
Also implicated in the wider New York scheme is an obscure but significant figure: Adnan el Shukrijumah, a former Florida resident sought for a decade by FBI agents who describe him as a leading al-Qaeda planner.
The U.S. indictment also mentions Rashid Rauf. The British citizen was linked to a 2006 scheme to use bottles of liquid explosives to blow up 10 passenger jets as they left London for North American cities.
Reports suggest Mr. Rauf has since been killed by the U.S. Central Intelligence Agency drone planes that strike terrorism suspects in lawless tribal regions of Pakistan, which remains a haven of sorts for al-Qaeda.