The Trans-Canada Highway has reopened after a fiery crash between two trucks in Kenzieville. ((CBC))

A section of the Trans-Canada highway in northern Nova Scotia closed overnight by a fatal accident reopened early Thursday morning.

But Cathy MacIsaac, spokeswoman with the provincial Transportation Department, said traffic will be reduced to one lane mid-morning Thursday, and will likely last about two hours.

"The cleanup did continue overnight. Earlier this morning, it was opened to traffic," she said Thursday. "However, later this morning we do expect it to go down to one lane as the investigation continues."

Police are continuing their investigation of the crash on Highway 104 near Kenzieville, between New Glasgow and Antigonish, which happened around noon Wednesday.

Two people died when a pick-up truck collided with a tanker truck carrying motor oil.

Thick black smoke billowed for hours after the accident because fire crews did not want the oil or fire suppressing foam to pollute the river.

The highway was closed between exits 27 and 29, and traffic was re-routed along Highway 4.

Explosions from the fire could be heard from kilometres away and the smoke was so thick and intense the tanker truck wasn't even visible in the bushes at the side of the road.