Four Canadian soldiers were wounded and a teenage Afghan boy was killed Sunday in a suicide bomb attack on a military convoy in Kandahar City, Afghan officials said.

The soldiers were taken by helicopter to Kandahar Airfield for treatment. Officials told CBC News they were in fair condition and were expected to resume their duties soon.

The boy who died was on the roadside when the blast occurred. Two other boys at the scene were wounded.

The car containing the bomb was parked by the side of the road, waiting for the convoy to pass, Afghan officials said. There are construction projects in the area, including a bridge Canadian engineers are helping to build.

NATO soldiers cordoned off the site of the attack, which happened near the house of the ousted Taliban's leader, Mullah Mohammad Omar, currently used as a base for the alliance.

The Canadian troops were travelling in armoured vehicles at the time of the explosion.

Less than an hour after the attack, a bicycle bomb went off near an Afghan police checkpoint near the city centre, but no one was injured, officials said. The device had been planted in the seat of the bicycle.

With files from the Associated Press