SANDY CREEK, N.Y. (AP) - State police say four people are dead after two cars slammed under a milk tanker truck that jackknifed when the driver swerved to avoid deer on a central New York highway.

Police say the tanker jackknifed across both northbound lanes of Interstate 81 in Oswego County around 11:30 Wednesday night.

Trooper Jack Keller says two vehicles slammed into the truck and skidded beneath it, killing all four occupants. The truck driver wasn't hurt.

Names and ages of the victims haven't been released. Keller said the three occupants of one car were from St. Lawrence County in northern New York and the other victim was from out of state.

The accident in Sandy Creek, 40 miles north of Syracuse, forced the closure of the four-lane highway for about seven hours.