An overturned tractor-trailer closed all lanes of I-85 southbound in Gwinnett County for several hours Sunday morning.

Lanes were closed south of Ga. 211 near the Barrow County line in the Braselton area from about 4:15 a.m., fire officials said.

Lanes were reopened at about 11 a.m.

Southbound traffic was diverted to Ga. 211 during the closure.

The single-vehicle accident occurred just after 4 a.m. when a tandem hauler -- a semi truck pulling two trailers -- jackknifed. The truck was hauling a 55-gallon drum of flammable liquid, ethyl acetate, that did not leak, but it took hours for wreckers to adjust the toppled trailer so its cargo could be inspected by a hazmat crew.

The driver of the truck was treated at the scene for minor injuries.