An official with Canada's spy agency has said that potential terrorists already reside inside the country, and that some have been schooled in al-Qaida training camps.

Jack Hooper, the deputy director of the Canadian Security Intelligence Service, spoke Monday in Ottawa to a legislative committee studying Canada's involvement in Afghanistan.

Hooper told the lawmakers Canada faces a threat from home-grown terrorists. He said that all the circumstances which produced the London transit bombing are present now in Canada.

Hooper said that many of the home-grown terrorists are Canadian citizens.

He also cautioned that his agency has been able to investigate only 10 percent of the immigrants who have come to Canada during the past five years from Pakistan and Afghanistan.

Some information for this report was provided by AP and Reuters.