Commuters on the A12 in Essex faced heavy congestion last night after two serious crashes in the county.

A man was arrested on suspicion of causing death by dangerous driving after two people were killed in a pile-up on the M11 near Harlow, Essex Police said.

The five-vehicle collision involved a horse box from the famous trainer Brian Meehan’s stables. The trailer carrying five horses from the stables collided with three cars and a lorry shortly after 2.15pm in a smash that left the northbound carriageway closed between junctions seven for Harlow and eight for Bishops Stortford and Stansted Airport.

Essex Fire and Rescue said it had to free three people trapped in cars and five horses were released from the horse box.

The horses were rushed to the Newmarket Equine Centre where they were being assessed by vets for injuries, according to a statement on Meehan’s website.

It is not yet clear if they were hurt in the crash or if any of the animals will need to be put down, but the trainer’s three intended runners at Newmarket on Thursday evening were withdrawn.

The carriageway was completely blocked for several hours, and remained closed for most of the night.

Meanwhile, a three-vehicle collision involving two lorries and a car on the A12 Chelmsford southbound bypass at 4.30pm forced the London-bound stretch of road to close.

Engineers had to clear a large amount of oil which spilled on to the stretch of road between junction 17, A1114 (Howe Green) and junction 16, B1007 (Galleywood).

An Essex Police spokesman said one motorist involved in the collision suffered injuries not thought to be life-threatening.

Paramedics were called to the scene to treat the injured motorist. It is not known if they were taken to hospital.

The bypass is tonight still closed. Diversions are in place. Traffic heading for the M25 can divert via the A130 and A127.

Four fire engines attended the scene. A brigade spokesman said: “Crews were called to assist at the scene of a road traffic collision involving two lorries and a car on the A12 southbound carriageway, between Howe Green and Galleywood.

“Firefighters arriving at the scene reported that no-one was trapped but a significant amount of diesel had spilled on to the roadway. Crews laid a foam blanket over the spillage and made vehicles safe before leaving the scene.

“The road was closed as emergency service teams worked, creating significant congestion during rush hour.”

Following the M11 crash, an Essex Police spokesman yesterday said: “Two people in a car have died and the driver and passenger in another car have been taken to hospital in Cambridgeshire.

“A woman has serious internal injuries and was flown by air ambulance and a man was taken by ambulance with a head injury.”

He added: “The carriageway is completely blocked and is impassable.

“The road will remain closed throughout the afternoon and into the evening.

“Motorists are advised to avoid the area and find alternate routes.”

A statement posted on Meehan’s website read: “There were two other horses accompanying our three runners to Newmarket.

“One was the coloured pony we use to lead some horses down to the start, the other was a horse on his way home.

“Details are still unclear, but they were all taken to the Equine Centre for assessment by the vets, and we do not know the extent of any injuries at the moment.

“It is obviously very upsetting for everyone concerned, but they could not be in a better place to receive the care they need.”

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