Oxford United chairman Firoz Kassam has reassured fans it will be safe to attend next Sunday's FA Cup derby with Swindon.

Reassurance: Firoz KassamHis words came after trouble marred United's 1-0 third division win over Lincoln at the Kassam Stadium on Saturday.

Around 25 spectators, seemingly looking for a fight, invaded the pitch after the final whistle, running towards Oxford fans in the North Stand.

Stewards prevented them getting at the home supporters. There were no arrests as many of the hooligans got away from pursuing police, who scrambled the police helicopter to help them in their search.

Some fans have been critical of the stewards, claiming they were slow to react and saying the trouble is a big worry, with the potentially volatile local derby with Swindon only days away.

Many supporters feel that safety officer Tony Ashley was naive to play down the possibility of any trouble when Oxford-Swindon derbies sadly have a history of it.

Yet Kassam insisted: "There will be plenty of police around for the Swindon match - it's a Category A game.

"I watched the pitch invasion today and I was very disappointed with it. But I can reassure people we will do everything we can to make the Swindon match safe for spectators, and there will be a big police presence.

"We are not naive . . . Tony Ashley and (secretary) Mick Brown have been around a long time."

Kassam said that, while the income generated by the televised FA Cup second-round tie would be very welcome, police costs would be between £16,000 and £20,000.

There were reports that some of the fans who invaded the pitch were from the Swindon area, though it is hard to believe they could be Swindon Town fans, as the second division club had a home game on Saturday.

Ashley said: "I cannot say a lot because it is now under investigation by Thames Valley police, but no Oxford fans were involved."

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