North Yorkshire Police has confirmed that the A19 north of Askern is currently closed in both directions following the collision.
A spokesman said: “Emergency services are currently at the scene of a serious collision on the A19 near Womersley Mill, Whitley, in the Selby District.
“It occurred at around 10am and involved a lorry and a car.
“Local diversions have been put in place. Motorists are advised to avoid the area until further notice.”
Eyewitnesses have reported two air ambulances at the scene as well as numerous emergency vehicles.
The road is understood to be closed near to the junction with Highfield Lane.
Witnesses or anyone with information that could assist the investigation are asked to call North Yorkshire Police on 101, select option 1, and speak to the Force Control Room. Please quote reference NYP-04102021-0117.