Police from Ukraine and the Czech Republic broke up a gang that brought women from Ukraine and forced them into prostitution in Eastern Europe, police officials said on Thursday.

Police in Ukraine's western Lviv and Zakarpattia regions, together with Czech colleagues, detained the group in the Czech Republic town of Frantishkove Lazne, close to the German border, an Interior Ministry spokesman said.

Police freed four women brought from Ukraine and arrested the owner of a restaurant where the women were allegedly kept. Several passports belonging to other victims of the sex trade were found in the owner's office, the spokesman said.

Police refused to give further details, saying an investigation was underway.