Two Canadians were among the four aid workers kidnapped in an attack at a Kenyan refugee camp near the border with Somalia, a security official said Saturday.

The Kenyan official, familiar with the case but not identified, confirmed the nationalities of the victims and said one of the Canadian passport holders was of Pakistani origin.

The two others kidnapped in the Friday attack were from Norway and the Philippines.

The incident also left a Kenyan aid worker dead, police official Philip Ndolo said in an earlier report.

The kidnappers are believed to be Somali militants who ambushed the two-car convoy the aid workers were driving through the Dadaab refugee camp, he said.

Ndolo also said that a security escort had originally been arranged to accompany a high-ranking delegation from the Norwegian Refugee Council, but that the aid group decided at the last minute to travel through the Dadaab refugee camp without an armed escort.

Council secretary general Elisabeth Rasmusson was present during Friday's attack but was not harmed.

Rasmusson said Friday that the attack happened on a main road toward the city of Dadaab in “what is recognized as the safe part of the camp.”

She said four men with pistols carried out the attack against the two vehicles. The attackers only took one of the vehicles.

Foreign Affairs has not yet confirmed that Canadians are among those taken captive, but issued a statement Friday saying the agency was aware of a “reported kidnapping.”

“We are pursuing all appropriate channels to seek further information and are in close contact with Kenyan authorities,” the statement said.

“We will not comment or release any information which may compromise these efforts.”

Militants have penetrated Dadaab several times over the last year.

Last October, gunmen kidnapped two Spanish women from Doctors Without Borders.

The two are still being held, most likely in Somalia. Several roadside bombs, most of which targeted police, have also exploded in the camp over the last year.

A spate of cross-border attacks last year, including around the resort town of Lamu, is the reason Kenya gave publicly for its military push into Somalia last October to target Islamist militants from the group al-Shabab.

With files from The Associated Press