OTTAWA - Two Canadian aid workers and their two colleagues are safe and sound Monday after Somalian and Kenyan troops rescued them from armed kidnappers.

Canadians Steve Dennis, 37, and Qurat-Ul-Ain Sadazai, 38, along with Glenn Costes, 40, of the Philippines, and Astrid Sehl, 33, of Norway, were snatched by gunmen Friday in a brazen attack in the Dadaab refugee camp in Kenya.

All four work for the Norwegian Refugee Council (NRC), which released a joint statement from their families Monday confirming the missing men had been rescued and are now in the Kenyan capital of Nairobi.

"We also want to express our gratitude for all the support, help and warm thoughts we have received during this very trying time," it said.

In a statement, foreign affairs said it was "elated" to hear the two Canadians were safely rescued.

The Canadian government also acknowledged the dedication and sacrifice of all humanitarian aid workers who risk their lives to help some of the world's poorest people.

Two other members of the convoy were injured in Friday's attack and a Kenyan driver, Abdi Ali, was shot and killed.

Despite the harrowing few days, NRC director Rolf Vestvik said Monday his agency wants to continue to bring water, education and shelter to the roughly 460,000 residents of the sprawling refugee camp.

"We hope we still will be able to operate in Dadaab," Vestvik said.

The aid workers were held hostage inside Somalia and rescued when Somalian government soldiers stopped a vehicle near the Kenyan border carrying supplies for the kidnappers on Sunday, Reuters news agency reported.

The troops seized three occupants, who directed them to the hostages, who were freed following an overnight firefight.

Kenyan military spokesman Col. Cyrus Oguna said the two armies launched a joint operation over the weekend after learning the four aid workers were being held near the border. Oguna said the four were unharmed but exhausted.

The Dadaab refugee camp was set up in 1991 and houses mostly Somalis who fled the ongoing civil war in their country and widespread food shortages in the region.

The security situation in the camp has been a growing concern in recent months.

Last October, two Spanish aid workers with Doctors Without Borders were kidnapped from Dadaab and are still being held in Somalia. That month, Kenya sent troops into Somalia to help fight the Islamist al Shabaab militant group, which is feared to have infiltrated the camp.

--with files from Reuters