A group of drunken youths thought they had picked an easy target when they decided to disrupt a brass band's open-air concert watched by a crowd of pensioners. But they thought again when the band struck up the theme from The Great Escape and - as one - a "Dad's Army" of around 20 war veterans rose from their deckchairs and advanced towards the mob, prompting them to turn on their heels and flee.

Les Brown, 78, a former RAF pilot who served in Egypt during the second world war, said: "We got so fed up with these little toerags, some of us decided to stop them. The Great Escape music came on and I looked round and caught glimpses of other people obviously thinking the same as me. We stood up and kissed our wives and marched towards them. It felt like I was back in the war, coming up against a fierce foe.

"But we were a determined lot. We might be old, but these youngsters didn't stand a chance in hell. I've never seen a group of young men look so scared as when we started advancing."

The showdown flared in Weston-super-Mare, Somerset, on Sunday, as the yobs - aged between 18 and 25 - spilled out of pubs after the World Cup.

They descended on Grove Park, carrying crates of beer and began playing football close to the bandstand where the Redland Wind Band was entertaining around 300 people. It continued to play - until a ball was launched at the conductor, who halted the performance.

The band provided a suitably stirring tune as the pensioners, some with sticks, others on Zimmer frames, advanced on the 30-odd youngsters shouting: "Forward!" and "Away with you!" To the surprise of some, they obeyed.

John Horler, 60, who runs the cafe in the park, said: "Suddenly, about 20 of us, mostly aged 60 or 70, got up from our chairs and advanced. It was amazing - totally spontaneous - and the kids could see we meant business. It was like a scene out of Dad's Army. Maybe it was the Dunkirk spirit that spurred us all on."