Ottawa — The gunman in Wednesday’s attack on Canada’s capitol had a criminal record and recently applied for a passport, planning to travel to Syria after undergoing a “radicalization process,” police said on Thursday.

Michael Zehaf-Bibeau, 32, was a Canadian who may also have held Libyan citizenship, said Bob Paulson, commissioner of the Royal Canadian Mounted Police (RCMP). He said the suspect had no apparent links to another Canadian who killed a soldier in Quebec earlier in the week.

Zehaf-Bibeau fatally shot a soldier at a national war memorial in the capital Ottawa on Wednesday before racing through the parliament building where he was shot dead near where Prime Minister Stephen Harper was meeting with lawmakers.

Born in Montreal to a father from Libya and a Canadian mother, Zehaf-Bibeau had gone on to live in Calgary and Vancouver, police said.

“We need to investigate and understand his radicalization process. He is an interesting individual in that he had a very well developed criminality,” Paulson said. “There is no one path or one formula to radicalization.”

The RCMP had only learned of the suspect’s interest in traveling to Syria when it interviewed his mother on Wednesday, the commissioner said.

U.S. officials said on Wednesday they had been advised Zehaf-Bibeau was a convert to Islam, the same as the assailant in Monday’s attack, Martin Rouleau, 25, who ran over two Canadian soldiers with his car. Both attackers were shot dead.

“We have no information linking the two attacks this week,” Paulson told reporters in Ottawa, which remained on high security alert. He said police expected to swiftly determine whether Zehaf-Bibeau received support in planning his attack.

Zehaf-Bibeau had recently applied for a passport and had arrived in Ottawa on Oct. 2 to try to speed that process, but checks by the RCMP did not turn up any evidence of national security-related criminality despite criminal records indicating infractions related to drugs, violence and other criminal activities, Paulson said.

The commissioner said Zehaf-Bibeau’s email was found in the hard drive of someone charged with what he called a terrorist-related offense.

Zehaf-Bibeau was not one of a group of 93 people the RCMP are investigating as “high-risk travelers,” he added.

Underscoring tensions on Thursday, armed police arrested a man who tried to approach the shooting site just as Harper, the prime minister, was laying a wreath to commemorate the slain soldier.

Harper said the attack would only strengthen Canada’s response to “terrorist organizations.”

On Tuesday, Canada sent six warplanes to the Middle East to participate in U.S.-led air strikes against Islamic State militants who have taken over parts of Iraq.

Harper pledged to speed up a plan already under way to bolster Canadian laws and police powers in the areas of “surveillance, detention and arrest.”

The attacks prompted U.S. officials to consider steps to tighten controls on the border with Canada and make it easier to revoke the passports of suspected militants, but officials cautioned the talks are in preliminary stages.

A woman who identified herself as the suspect’s mother issued a statement earlier on Thursday apologizing for her son’s apparent actions.

“No words can express the sadness we are feeling at this time,” said the woman, Susan Bibeau, in a statement provided to the Associated Press. “We send our deepest condolences.”

Zehaf-Bibeau stayed at a homeless shelter in a downtrodden part of Ottawa for at least a week before the attack, multiple people at the site said on Thursday.

A friend, Steve Sikich, who had lived with Zehaf-Bibeau at a Vancouver homeless shelter said Zehaf-Bibeau had rambled about wanting to travel to Libya and join the Islamic State. “He didn’t seem like a bad guy,” Sikich said.

Police have interviewed some of the people who were at the Ottawa shelter but none of the people with whom they spoke said they had any knowledge of his plans.