The M25 was closed for hours due to a serious crash involving a car.

The anticlockwise carriageway has been reopened but the clockwise carriageway remains closed.

Essex Fire & Rescue were on scene attempting to release a trapped person from the vehicle and air ambulance was in attendance.

A spokesman for the ambulance service said: "We received a call just before 2pm today to a road traffic collision on the M25 between junctions 29 and 30.

"Two rapid response vehicles, an ambulance crew, ambulance officer and air ambulance from Essex and Herts Air Ambulance were dispatched.

"They treated a woman, believed to be in her 30s, who had suffered a serious head injury.

"She was airlifted to Royal London Hospital in a life-threatening condition."

The fire service helped secure the scene after heading back from another job.

A spokesman said: "Firefighters were on their way back on attending the field fire near the M25 when they came across a road traffic collision on the M25 between junction 29 and 30 on the southbound carriageway.

"The road traffic collision involved one car.

"Firefighters worked with paramedics with release one casualty from the vehicle.

"The road was shut so firefighters and the Ambulance Service could deal with the incident safely. Fire crews left the scene at 2:45pm."

All lanes between j29 and j30 in both directions are now reopened after being closed to allow for the air ambulance to land in the carriageway.

A spokesman from Highways England said: "Traffic is being diverted and following the hollow triangle symbol.

"Motorists heading towards the area are advised to allow additional travelling time."

The lane closures are between J29 Southend Arterial Road (A127) and J30 and 31 (A282), meaning there are also delays on the A13 and the A127.

The crash was first reported at about 1.30pm but delays are expected to last well into rush hour, with normal traffic anticipated to resume by 5.45pm.

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