A driver was forced to pull over after a discarded cigarette, thrown from the window of another vehicle, set fire to his car.

The Citroen driver pulled off at Junction 6 of the M5 in Warndon Villages, Worcester, yesterday when he saw smoke coming from under his bonnet last night.

He immediately called the RAC who alerted Worcester Fire Station to the incident which took place in Parsonage Way.

After opening the bonnet, firefighters were surprised to discover a small patch of burning insulation material.

The bemused driver said he had seen someone in another car throw a cigarette out of the window, which appears to have entered the grille and set fire to material under the bonnet.

Alec Mackie, of Hereford and Worcester Fire and Rescue Service said: "This is an unusual and rare occurrence for which there could have been no other explanation.

"This just goes to show how easy it is for discarded cigarettes to start fires," said the service spokesman.

He added that he had only ever experienced one other case like this several years ago.

After the incident, which happened at about 6.40pm, the driver was able to continue safely on his journey.