Drivers are facing delays on the M4 near Reading after a crash led to lane closures close to Theale.
Two lanes were shut on the westbound carriageway between junction 11 for Reading and junction 12 for Theale following the collision.
Traffic monitoring service Inrix reported congestion building on the approach to the incident, with motorists warned to allow extra time for journeys.
The closures affected one of the busiest commuter routes for Reading, with queues forming as emergency services attended the scene.
Delays also impacted drivers leaving Reading via the M4 westbound, particularly during peak travel times.
It is not yet clear whether anyone was injured.
Lanes remained closed while vehicles were recovered and the carriageway cleared, with traffic expected to ease once the motorway fully reopened.
