OTTAWA -- Heavy fog and a controlled agricultural burn in Ottawa's south end created low visibility conditions in an area where several collisions were reported Thursday morning.

One of the crashes, at Barnsdale Road and Moodie Drive, west of Highway 416, involved a school bus. There are no reports of injuries.

Moodie Drive was closed between Barnsdale Road and Brophy Drive, and Barnsdale was closed between Twin Elm and Moodie for several hours. Police said there was poor visibility and "several minor collisions" in the area.

Ottawa fire tweeted just before 10 a.m. that firefighters located a controlled agriculture burn in the area west of Moodie Drive, which combined with heavy fog was contributing to the low visibility conditions in the area.