A WITNESS told last night how a teenager was engulfed in flames during a horrific bus depot accident.

Fifteen-year-old Scott Sargeant was described as poorly but stable by doctors at Newcastle's Royal Victoria Infirmary last night.

He was with 48-year-old Fred Wren at the Abbey Coaches compound, in South Bank, Middlesbrough, when it is thought sparks from a welding machine ignited paint thinners, causing an explosion.

Mr Wren, Abbey Coaches' manager, was continuing to receive treatment at theJames Cook University Hospital, Middlesbrough.

Stuart Tyreman, a worker at Town and Country Tyre Services, near the bus depot, told how he and his colleagues rushed to the pair's aid on Saturday, just after 1.30pm.

He said: "I heard a big bang. I couldn't see anything at first, but then I saw the young lad run outside - he was on fire.

"The gaffer told me to get some rags to help put him out. The lad was rolling about on the floor in agony. He was screaming - it was terrible.

"It was over in minutes, it just happened so quickly. The older guy was burned pretty badly too, because when I saw him he had no clothes on; they were all on fire."

Police are investigating the explosion and have informed the Health and Safety Executive, which yesterday started its own probe.

Michael Wearmouth, acting manager of Abbey Coaches, said: "At this stage, the only people who know what really happened are Scott and Fred.

"Scott's a young lad with a great interest in buses and mechanical things, so he often watches the lads while they're doing jobs in the workshop.

"Our thoughts are with Scott and his family and we hope he pulls through soon."