Chatham-Kent Police believe fog was a factor in a fatal crash near Tilbury Tuesday morning.

Two vehicles collided head-on along Queens Line between Sinclair Road and Highway 401 around 7 a.m.

One driver has died and the other suffered serious injuries.

The road was reopened around 1 p.m., following hours of investigation.

Environment Canada issued a fog advisory early Tuesday, warning some parts of southern Ontario could see "near-zero visibility."

All morning school bus runs in Chatham-Kent and Sarnia-Lambton were also cancelled due to the fog.