German police say they will do everything in their power to protect England fans if they are targeted by foreign hooligans at the World Cup.
Security was tight after fans were attacked in Italy last week
The pledge came from Frankfurt's police chief Achim Thiel after a meeting with the Football Association, Home Office and football supporters' groups.
England play their first match in Frankfurt against Paraguay on 10 June.
Reports have speculated that fans could be attacked by German, Dutch or Polish hooligans during the tournament.
On Tuesday 14 March, Middlesbrough supporters were attacked in Rome by local hooligans the night before the side's Uefa cup match with Roma. Three fans were stabbed.
In London on Wednesday, Dr Thiel and Frankfurt's mayor Achim Vandreike were upbeat after a meeting with UK authorities.
Dr Thiel said of the attack reports: "So far there is no information whatsoever about this.
"We are looking into it, pre-emptively, and if it should occur, of course we will do everything in order to protect English supporters against such possible attacks."
Mr Vandreike said they wanted the match to be a "big party" and Dr Thiel said the authorities would not be laying on any extra facilities such as additional prison cells in case of trouble.
"We don't envisage a situation where hundreds of English or Dutch fans, for example, would be arrested," he said.
They also contradicted German soccer legend Franz Beckenbauer, who on Tuesday urged England fans to stay away from the tournament unless they had valid match tickets.
Mr Vandreike said: "All supporters from England who want to come to Frankfurt are most welcome, we want to make sure they feel welcome in Frankfurt."
Fans without tickets could go to a public viewing area, he said.
He added: "All bars in Frankfurt have stocked up with enough beer."
England's first match is in Frankfurt
Dr Thiel confirmed performing a Nazi salute was an offence in Germany. UK authorities have called for England fans to treat their German counterparts with respect and remember why such a gesture is banned.
Asked whether people would be arrested for making the gesture, Mr Vandreike said: "We would like to request English supporters not to display this kind of behaviour, because it would really put a dampener on the overall atmosphere.
"We would like to tell supporters that everybody is most welcome, that they should not try to provoke German supporters, and say 'you Nazis', because that would create a bad image in the city and Germany overall."
Dr Thiel urged fans to turn up early for matches, saying they should be at the stadium two hours before kick-off so security checks could be carried out.
And he warned that tickets would bear a personal identity code related to a person's passport, so anyone without the appropriate personal identification would not get in.
"Identity is going to be checked, and checked with the ticket," he said. There will be two public viewing areas in Frankfurt, which between them can accommodate 30,000 people.
There will be a floating screen in the middle of the River Main, the officials said.