Toronto police have reopened both the northbound and southbound Don Valley Parkway ramps to the Bayview-Bloor ramp after an early-morning rollover crash involving two vehicles.

One driver is in custody and being investigated for impaired driving. Toronto paramedics say the crash sent three people to hospital: two with minor injuries, one with serious injuries.

Both the north and southbound ramps from the Danforth to the Don Valley Parkway were closed for hours after the crash. The off-ramps from the DVP to the Bayview-Bloor ramp were also closed.

Police advised drivers to avoid the area.

"It's going to cause heavy delays southbound," said Toronto Police Const. Clint Stibbe. "Anyone that would normally be attempting to get off at Bayview-Bloor are going to find that ramp closed. You can expect heavy delays throughout the morning rush hour."