Prime Minister Stephen Harper has acknowledged that Canadians have joined an international effort to free almost 300 schoolgirls kidnapped by a west African Islamic extremist group.
But details about the extent and duration of the involvement are being kept under a blanket of secrecy.
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The U.S. State Department said Tuesday that American surveillance planes have begun flying missions over a remote area of Nigeria as part of a mounting international effort to find and rescue the teenaged girls abducted by the violent jihadist group Boko Haram.
Washington has acknowledged that it is providing intelligence, surveillance and reconnaissance support.
Britain, France and China have also sent teams to Nigeria to help with the search.
The Harper government has been eager to be seen responding to the international outcry over the girls, but it will not say what equipment or personnel — civilian or military — have been committed to the fight.
"The kidnapping of these school girls by Boko Haram is obviously repugnant to everything we believe in as Canadians, and I think most people in the world believe," the prime minister told the House of Commons.
"Our hearts are obviously with these girls and their families. There are Canadian personnel who are now present in Nigeria and they are there provide liaison and to assist in Nigerian authorities in their search."
The statement came as Boko Haram, which is loosely interconnected with al-Qaeda, released a video which purportedly shows more than 100 of the schoolgirls abducted last month. The video was obtained by the French news agency AFP, but its authenticity has yet to be verified.
The girls are seen wearing hijabs and praying, while the leader of the group claims that they have all converted to Islam.
There are reports from the region that the Nigerian government is willing to discuss a prisoner exchange for the hostages.
Canada, the United States and other western countries have a policy of not paying ransom or swapping prisoners.
Appearing before the Commons defence committee Tuesday, the country's overseas commander, Lt.-Gen. Stuart Beare, refused to discuss what role Canada is playing in the crisis.
Central and west African nations, including Nigeria, Niger and Cameroon, have all been struggling to deal with the evolving threat of Boko Haram, which was founded in 2002 and opposes Western education. It also forbids Muslims from taking part in any political or social activity associated with Western society.
It has been linked to a number of deadly attacks and kidnappings in the region, including an April 14 bus-station bombing that killed at least 70 people, and May 2 car-park explosion where 19 people died.
As little as five years ago, it was believed Boko Haram was on the ropes because its charismatic founder, Mohammed Yusuf, was killed in Nigerian police custody, but it has regrouped and come back stronger.
Experts warned that by forging links with al-Qaeda in the Islamic Maghreb, which took over northern Mali in early 2013, Boko Haram was becoming a global player among extremist networks.
The kidnapping of the school girls is not a new tactic, but rather an extension of a smaller operation in May 2013 where women and children — including teenage girls — were taken hostage in response to the arrests of the families of Islamic fighters.
The crisis ended in a prisoner swap.