WARSAW, July 8 - A low-key Intertoto Cup match between Vetra Vilnius of Lithuania and Legia Warsaw of Poland was abandoned at halftime on Sunday after Polish fans attacked police with metal bars and stones.

The incident comes just 10 weeks after Poland were awarded the right to co-host the 2012 European championships with Ukraine by UEFA, European soccer's governing body, and could have wider implications.

Polish news agency PAP reported that some of the 3,000 travelling Legia fans attacked Lithuanian police during their second round, first leg match against Vetra in the Lithuanian capital.

The match was abandoned at halftime with Vetra leading 2-0.

Police used tear gas and water canons to try to disperse the hooligans and the battles continued for around 30 minutes. Nine Polish fans were arrested, the Baltic News Agency BNS reported in Vilnius.

UEFA will now be mounting an investigation into the incident which is without parallel in the competition, used as a qualifier for the opening rounds of the UEFA Cup.

PAP said Polish fans were armed with metal bars stones and flares. They smashed down the pitch side barriers and invaded the field during the halftime interval causing the match to be abandoned.

The president of Legia said he was shocked by the incident and that his club was prepared for the consequences.

"We are prepared for any decision UEFA will make," Leszek Miklas was quoted as saying by the Web site www.legia.net.

"I am really shocked that people from a civilised country can behave like this. These people are savages who cannot live in a normal society,"

Michal Listkiewicz, the chairman of Polish Football Association said the penalty for Legia would be "huge".

"A huge price will be paid for this and I do not rule out an exclusion from the cup," he told the Web site.

He also said that the match result would probably be revised to a 3-0 victory for the Lithuanians. The second leg is due to be played next Saturday.