As German police moved to provide first aid, Thomas said, members of the surrounding crowd threw glass bottles. The resulting brief melee, during which police in riot gear used pepper spray to control some in the crowd, resulted in the 13 arrests _ six fans for clashing with police and seven for fighting.

The fans were to be released later Tuesday and issued orders to leave the city, police said.

Following the scuffle, German police arrested eight Sweden supporters, Swedish police spokesman Lennart Petersson said. The Swedes were arrested not because of any altercation but because they have been involved in previous fights at sporting events and authorities didn't want trouble at Tuesday's game, he said.

The melee in Cologne was an exception at this World Cup. Since the tournament started June 9, hundreds of thousands of fans have watched games and partied; only an approximate 2,700 nationwide have been arrested or detained by police related to the World Cup, most for minor crimes, Thomas said.

Meanwhile Tuesday, in the central city of Hanover police were checking buses and other vehicles carrying fans from Poland, which was playing its last World Cup match against Costa Rica. Both teams already were eliminated because both lost their opening two matches.

Two known German hooligans were arrested at car parks on the city's outskirts, police spokeswoman Katharina Zwerg said.