A group of unidentified people attacked two minibuses carrying migrant traders Monday in Indonesia's restive Papua province, killing four and wounding nine, police said.
The attack in the provincial capital Jayapura came a day after 17 people were killed in clashes involving groups supporting rival politicians in another area in jungle-covered Papua, dpa reported.
The assailants in Monday's attack ambushed the vehicles and slashed the victims with machetes and other crude weapons before dawn, a provincial police spokesman said.
"This is a heinous criminal act and we are determined to arrest the perpetrators," said Wachyono, who like many Indonesians goes by one name.
Most of the victims were grocery traders who had migrated to Papua from the main island of Java, Wachyono said. A soldier was among the four people killed.
A witness told the state-run Antara news agency that the attackers fired shots.
"I was in a taxi, and I heard sounds of gunfire all of a sudden," Siti Aminah told the news agency.
On Sunday, men armed with bows, arrows and other weapons fought outside a local council building in the remote Puncak district, Wachyono said.
That clash erupted after the local election commission refused to register a candidate running for district chief in an election scheduled for November, he said.
The police spokesman said the incident was unrelated to Monday's ambush.
Papua, one of Indonesia's poorest provinces, is home to a low-level separatist insurgency.
It became part of Indonesia in 1969 after a UN-sponsored referendum that Jakarta was accused of manipulating.