A lorry loaded with cooking oil exploded in a ball of fire, causing chaos for drivers on the main London to Brighton road.

Flames shot 50ft into the air as the blaze engulfed the articulated truck, reducing it to a blackened shell in minutes.

Its contents, dozens of barrels of the highly-flammable oil, helped fuel the fire.

The explosion was so intense it shot a burning tyre across all four lanes of the A23 at Handcross Hill, just south of Crawley.

The lorry driver jumped out when he realised the engine was overheating and escaped uninjured.

The main route from Brighton to London was shut in both directions, causing long tailbacks.

The northbound carriageway of the A23 was reopened at 4.25pm. Traffic travelling south was diverted from the road at junction 11, near Pease Pottage.

Motorists were funnelled around Horsham, along the A264 and A24 or through Handcross on the B2114.

Inspector Mark Dunn, based at Haywards Heath's road police unit, said: "During peak hours the A23 was obviously very slow, with traffic stretching back to junction 10.

"Congestion had eased by the early evening."

Engineers from the Highways Agency worked through the night resurfacing a 100-metre stretch of all three lanes of the southbound carriageway, which was reopened at 6.10am today.

Mr Dunn said: "The fire was so severe it spread underneath the tarmac and we were concerned the road surface might have broken up under the weight of traffic."

He said: "Thankfully, the driver was okay. He had realised something was wrong and was in the process of detaching the trailer.

"As there was no hard shoulder, he had pulled up on the edge of the carriageway."

Sub Officer Peter Bristow, of Crawley fire station, said: "The biggest problem we faced was lack of water.

"There are no hydrants down the side of the motorway like a normal road. We had three appliances arrive initially with a small amount of water but had to make it up with other pumps, a foam tender and a bulk liquid carrier.

"When we first arrived, because of the intense heat, quite a few of the barrels of cooking oil were exploding.

"I had to make efforts to keep my crews safe by standing well away.

"The Environment Agency was also taking precautions to prevent any liquid running into the watercourse. The mixture of oil, water and foam is quite a concoction."

The truck is owned by KTC Edible Oils, in Wednesbury, West Midlands.

A spokesman said: "There were no injuries to the driver, thank God."