Unidentified Somali gunmen ambushed a U.N. convoy near Mogadishu's airport Wednesday, killing one Somali driver and wounding five other people, including a Canadian.

The gunmen also abducted and then later released unhurt a Somali official with the U.N. High Commissioner for Refugees.U.N. officials said Bill Lindsay, a Canadian security official, suffered a minor wound in one hand. Officials said Lindsay was the only expatriate worker for the U.N. Development Program still in Somalia.

Somali gunmen in two pickup trucks attacked the four-vehicle convoy as it attempted to move from the development program building to the airport, which was about half a mile away.

One Somali U.N. driver was killed and two other Somali employees were critically wounded. Lindsay and two other Somali workers suffered only minor injuries, officials said.

The ambush came just days before American troops plan to move ashore to protect the final withdrawal of remaining U.N. peacekeepers in Somalia.

Most international aid workers and civilian U.N. employees have left the country, at least temporarily, to assess the security situation after the pullout of the last U.N. troops.