One person is dead and another in critical condition following a crash on the 401 off ramp at Wellington Road.

OPP say the vehicle went into a ditch off the east bound ramp around 12:20 p.m. Wednesday.

A female and male were both taken to hospital, with the female pronounced deceased.

OPP Sgt. Dave Rektor says one person was ejected from the vehicle.

The ramp was closed for an investigation to determine the cause of the collision. 

"We're trying to figure out why the driver went straight (off the ramp) instead of turning," Rektor said.