One person is dead after a horrific crash during the morning rush hour on Highway 427.

A tractor trailer slammed into several cars at around 9 a.m. this morning. Traffic had started to slow down in the collector lanes but the truck couldn't stop on time and plowed into three vans and an SUV.

The driver of one of the vans never stood a chance.

"The van was completely crushed," OPP Sgt. Cam Woolley told CTV Toronto from the scene.

The driver of that van was killed and five other people were taken to hospital for treatment.

The accident, which happened on the highway's northbound lanes near the Burnhamthorpe exit, closed down the northbound collector lanes at Dundas and closed off northbound ramps at Evans Avenue and The Queensway.

The highway was closed as far back as Dundas Street for most of the day and traffic slowed to a crawl in the opposite direction.

The northbound collector lanes opened before 5 p.m., more than seven hours after the accident.