The Royal Canadian Mounted Police announced Monday that it had arrested Suliman Mohamed, 21, and charged him with participating in the activity of a terrorist group and conspiracy to participate in a terrorist activity.
After making the arrest, Canada's national security team said in a statement that Mohamed's arrest was directly linked to the arrests of Ashton and Carlos Larmond, two Ottawa brothers accused of conspiring to commit terrorism offenses. The brothers were arrested Friday.
The RCMP alleged Mohamed conspired to participate in terrorism with the Larmond brothers.
"These recent arrests underscore the reality that there are individuals in Ontario and in Canada who have become radicalized to a violent ideology, and who are willing to act upon it," wrote Chief Superintendent Jennifer Strachan, criminal operations officer for the Ontario Division of the RCMP.
After an investigation dating back to at least August 2014, the Larmond brothers, both 24, were arrested Friday in two different locations. Ashton Larmond was arrested in Ottawa, but his brother Carlos was arrested at Montreal's Pierre Elliott Trudeau International Airport, where police said he was intending to travel overseas for terrorist purposes.
Carlos Larmond was charged with participation in the activity of a terrorist group and with attempting to leave Canada to participate in terrorist activity abroad, a relatively new Canadian terrorism law.
Through their lawyer, the brothers indicated they would be fighting the charges. The RCMP statement did not give details of allegations against the suspects.
"I don't think we've been shown anything at this point," said Richard Addelman, the lawyer representing the Larmonds.
It was not clear Monday night if Mohamed had retained an attorney.
Canada's terrorism laws were amended in April 2013 to include an offense for anyone leaving or attempting to leave Canada for the purpose of committing a terrorist act abroad. Very few Canadians have been charged in this way and the outcome of this case will be closely watched by counterterrorism officials.
"It's going to be a significant case, that's for sure," added Addelman.
Neighbors in an east Ottawa neighborhood where Mohamed has lived said they did not immediately recognize him but indicated there had been police activity on the street all weekend long.