A fatal crash involving "at least" three vehicles, including a tractor-trailer, shut down Highway 401 in both directions east of Brockville for hours on Sunday, according to Ontario Provincial Police.

Police were called to the scene just before 2:30 p.m. One person was pronounced dead and two others were seriously injured.

The highway was closed at kilometre marker 705 for east bound traffic and kilometre marker 716 for westbound traffic, causing traffic jams.

OPP said the highway reopened at about 1 a.m. Monday.

No other details about the crash were immediately available.