Canada is concerned about the national security threat posed by its citizens, who joined the Islamic State group, returning to the country. Prime Minister Justin Trudeau in Parliament yesterday pledged to prosecute those who broke the country's anti-terrorism laws by joining the IS group. <br/><br/>He also said his government would try to reintegrate such persons into society. According to government figures released in 2016, nearly 180 Canadians are known to have travelled overseas to join the IS group. About 60 have returned to Canada. Only two returnees have been prosecuted the country's anti-terrorism act, so far.