A woman in her 20s is dead after a vehicle rolled over on Highway 403 in Mississauga on Saturday, according to paramedics.

Emergency crews were called to the crash, in the westbound lanes shortly after the exit for Winston Churchill Boulevard, shortly before 12:30 p.m.

Paramedics pronounced the woman dead at the scene and transported a second woman, also in her 20s, to a local hospital for treatment of what were described as "moderate" injuries.

Highway 403 westbound is closed at Winston Churchill Boulevard, according to a tweet from the OPP. The lanes are expected to reopen by 4 p.m.