DALLAS, Texas -

Dallas police say six people were killed in a single-vehicle wreck after their speeding car crashed into a tree.

Police say four people died at the scene of the Sunday night wreck in southeast Dallas. Two others died at the hospital.

Officer Monica Cordova says when the back tire of the passenger side of the Chevrolet Impala traveling south hit a curb as the road curved, the driver lost control. The vehicle then slide across the southbound side of the road's three lanes and hit a tree in the median.

She said alcohol was not a factor, but speed was.

Names and ages of the victims have not yet been released.