The QEW has reopened after a major crash in Burlington that sent eight people to hospital Tuesday afternoon and closed lanes in both directions for several hours, snarling traffic.

The crash happened around 2:30 p.m. sending numerous emergency vehicles, police and paramedics to the scene at Guelph Line. After several hours of being shut down, police reopened the Fort Erie bound lanes of the QEW at Walkers Line a little after 5:30 p.m.

All eastbound lanes headed to Toronto were closed at Brant Street, but reopened around 6:30 p.m.

CLEARED Collision: QEW Toronto bound at Guelph Line <a href="https://twitter.com/hashtag/BurlON?src=hash&ref_src=twsrc%5Etfw">#BurlON</a>- All lanes now OPEN ^jp <a href="https://t.co/dmRyema6Ll">pic.twitter.com/dmRyema6Ll</a> —@OPP_GTATraffic

"What we're dealing with is apparently a single vehicle collision rollover with multiple patients," OPP Sgt. Kerry Schmidt said from the scene, mid-afternoon.

Police say that eight people were taken to hospital — two people are now in critical condition, and another person is in serious condition.

"Right now there are people fighting for their lives in hospital," Schmidt said.

All Toronto-bound lanes on the QEW are closed after a collision near Guelph Line. (David Ritchie/CBC)

"The vehicle came to rest on its roof on the [Toronto-bound] lanes of the QEW," Schmidt said. It appears that the vehicle involved in the crash was an eight-seater van.

"Unfortunately, I know this will be somewhat of a lengthy investigation, due to the fact that patients were located in different locations across the highway," Schmidt said.

The QEW was jammed up all the way through Burlington and into Hamilton for quite some time, Schmidt said.