Update: Two airlifted to hospital and two more taken by ambulance after crash

Several people have been taken to hospital after a crash this morning.

Police were called to a smash, which has been described as "very serious", at 6.20am in Hemel Hempstead Road near Redbourn.

A number of vehicles were involved, believed to be three.

An air ambulance was also called to the scene.

The incident happened close to the junction of Aubrey Lane.

Hertfordshire Fire & Rescue confirmed four people were trapped in vehicles and cutting equipment was needed to get them free. Three people were rescued from a Proton.

Police have confirmed that casualties have been taken to a couple of nearby hospitals but their injuries are unknown.

The road remains closed and the crash caused very long delays on surrounding routes this morning.