A QUICK-thinking motorist helped to prevent a major incident after noticing flames licking from the rear of a petrol tanker.

The motorist phoned the emergency services and fire crews were on the scene within minutes on the M4 in Newport. They doused the fire - which destroyed the back axle of the truck - using a foam jet.

Nobody was injured. The incident happened at 1.30pm on the eastbound carriageway of the M4 between junctions 28 and 27 near the High Cross turnoff in Newport. Police believe the consequences could have been worse had it not been for the rapid response of the South Wales fire service.

The38-tonne petrol tanker contained more than 20 tonnes of heavy oil. Gwent police Inspector Mike Cotterell praised the fire service for its prompt action in dousing the fire, which started after the lorry's brakes had seized. Inspector Cotterell said the incident may have been very serious had the container been carrying a different fuel. He said: "The heavy oil is not as combustible as petrol." Because of the extent of the damage to the tanker, police had to tow it from the scene.

Traffic police closed the near-side lane of the carriageway during the incident. It caused "minimal disturbance" to passing traffic, according to the police.

*PICTURED: A recovery vehicle prepares to tow away the tanker after it caught fire.