Two people were sent to hospital following a rollover crash on the QEW in Niagara-on-the-Lake, just east of St. Catharines.
OPP revealed the crash in a social media post just after 7 a.m. on Thursday involving a single vehicle.
The car was travelling in the Toronto-bound lanes of the QEW near Glendale Avenue before leaving the roadway.
Police are asking drivers to approach the area with caution amid an ongoing investigation.