Jakarta – Election violence hit several towns on the fourth day of the country's electoral campaign.

In Pekalongan, a coastal town in northern Central Java, supporters of the ruling Golkar party clashed with those of the Muslim-led United Development Party (PPP) on Wednesday, leaving five people injured and several buildings damaged, Kompas said.

Police in Pekalongan declined to comment when contacted on Thursday.

The clash broke out after PPP supporters stumbled on Golkar supporters who were removing PPP flags on the side of a road, the newspaper said. A government office and five other buildings were damaged in the melee that followed.

About 3,000 Golkar flags have disappeared from the streets of the town that has seen several clashes between supporters of the two parties since March.

In Yogyakarta, also in Central Java, the local PPP chapter halted campaigning after one of its offices was pelted with stones and attacked by Golkar supporters.

The Yogyakarta PPP chapter also decided to take down all the party flags, signs and posters that had been put up for the campaign in the city, to show support for the chapter's decision to halt campaigning.

In Pontianak, West Kalimantan, five supporters of the small nationalist alliance Indonesian Democracy party were injured after they were attacked by an unidentified group of men.

Golkar campaigned in several towns around North Sumatra and the Western Lesser Sunda islands, while PPP addressed supporters in Sulawesi and Kalimantan, the Indonesian part of Borneo island.