Two separate political clashes in Indonesia's eastern provinces of Papua leave 21 people dead, four months ahead of local elections.
Gunmen opened fire on a crowded minibus killing four people and wounding at least seven others on Monday in Abepura district.
At the weekend, a clash between supporters of competing politicians killed 17 people in Puncak district.
Papua is home to a huge copper and gold mine, and to a separatist insurgency.
The worst recent violence, in the recently created district of Puncak, saw rival clans fight each other with bows and arrows, rocks and machetes.
Mobs set alight houses and cars during the battle before police could restore order.
"We've deployed dozens of police and military to secure the area. The situation is tense but under control," said the local police chief Alex Korwa.
Puncak will hold its first local elections on 9 November. The fighting, which started on Saturday and went into Sunday, was between backers of the political rivals, Simon Alom and Elvis Satuni.
The more recent, but less deadly violence in Abepura might be linked to the separatist insurgency led by the Free Papua Movement (OPM), police said.
Papua's provincial police spokesman Wachyono (using one name) told reporters that attackers had blocked a road and opened fire on the minibus.
"Four people, including a military officer, were shot dead. At least seven others were injured after being attacked with sharp weapons, possibly axes and machetes," he added.
"We're still investigating the group's identity, what weapons they had used and what their motive was."
Rich in resources, its various peoples often feel ignored by the central government in Jakarta.
The OPM is small, under-funded and lacks sophisticated weapons but is a persistent irritant on the side a a more broad-based but peaceful movement for a re-examination of Papua's status in the Indonesian state.
A controversial "Act of Free Choice" overseen by the United Nations saw the huge area, formally part of the Dutch empire, come under Indonesian sovereignty in 1964.