Teenage yobs terrorised a 74-year-old grandfather who has been a charity Santa Claus for 16 Christmases.

Sydney Austin works for free bringing joy to children and raising cash for good causes.

His reward was to be harassed by a gang whose idea of fun was to run off with his specially made hat and fling it into a muddy gutter.

His ordeal happened on Friday evening as he was getting into a taxi outside Laurels First School in West Durrington after a charity Christmas fair.

A gang of about six youths aged about 15, who had earlier been thrown out of the event for unruly behaviour, ran up behind him. He saw them coming and tried to escape into the safety of the cab.

He had just climbed inside when a teenage girl reached in and yanked his Santa hat off.

She ran off with Mr Austin's taxi driver in pursuit. Eventually the girl dropped the hat in a gutter where it was retrieved, soggy and dirty.

After the teenagers were thrown out by school staff for running riot and shouting, they were seen hanging around the school gates until Mr Austin emerged.

Mr Austin, who lives in Broadwater, Worthing, had been entertaining 350 children and parents for two hours.

The retired newsagent said: "I was annoyed at what happened and dead worried because without that hat I wouldn't be able to do my other work for groups like the Worthing Lions.

"It's a shame when things like that happen. The group had been there all night worrying the school teachers.

"I've been going to that school every Christmas for the past eight years and I've never seen anything like it.

"What surprised me most was that it was a girl who pulled my hat off. I turned round as she did it and she was laughing like a drain. She ran off and chucked it under a car. I was a bit shaken up.

"I had the whole outfit made for me several years ago and I really take care of it. The hat was specially made.

"I do all of the work for free so I can't afford to go out buying new ones."

But the hooligans have not deterred Mr Austin from carrying on the role he loves.

He vowed: "What happened won't put me off. I've been a Santa for so long now."

During the weekend youths targeted the school again when they stole new equipment from a play area and scrawled the words, "We've been here. We thought you'd like what we've done," across a blackboard.

Head teacher Alan Matthews said: "What happened on Friday night was very unpleasant. The teenagers' behaviours was threatening, especially because there was a gang of them.

"We have a lot of problems generally with graffiti and damage to windows but I don't know if it's the same group. At the weekend someone climbed over the roof and into our internal quadrangle and stole some of the play equipment worth £1,000.

"We've had constant problems with poor behaviour over the summer with 13 windows covered in graffiti at one point.

"What happened at the weekend is typical of the incidents we have around here now. The message left by them on the blackboard was very cheeky. I don't know if it was done by the group who accosted Mr Austin."

Despite the disturbance, £1,900 was raised for the school by Friday's fair.

Police are investigating both incidents.