Two people are dead after a two-vehicle collision on Highway 401 west of Milton Sunday evening.

Emergency crews were called to the eastbound lanes of the highway approaching Guelph Line just before 9 p.m.

Ontario Provincial Police Sgt. Kerry Schmidt said witnesses told police that they saw a silver SUV driving erratically at a high rate of speed.

He said the SUV partially came to a stop on the shoulder, partly blocking the right lane. A short time later, a transport truck collided with the vehicle.

Two occupants of the SUV were pronounced dead on the scene, Schmidt said.

The eastbound lanes of the highway are closed between Highway 6 South to Guelph Line while police investigate.