Burundi’s police said it clashed with armed men in the capital, Bujumbura, killing three, in the latest violence to rock the East African nation.

The gunmen tried to ambush a car belonging to security officer General Christophe Manirambona on Friday, Domitien Niyonkuru, director of police in Bujumbura, told reporters in the city. Manirambona wasn’t in the vehicle and nearby police officers intervened to fight the assailants, he said.

Police showed reporters three bodies and weapons they said the assailants had carried. Niyonkuru said two people were arrested in connection with the attack and an investigation is under way.

Burundi officials have been targeted before in violence the United Nations says has left at least 277 people dead since April. In early August, the country’s former intelligence chief General Adolphe Nshimirimana was killed in an ambush in the capital, while a former army chief of staff was assassinated about two weeks later.

The country, home to 6 percent of the world’s nickel reserves, has been roiled by more than seven months of unrest since President Pierre Nkurunziza said he’d seek a third term in office. The president’s opponents say his July re-election violates a two-term limit set out in peace accords that ended 12 years of civil war in 2005. More than 200,000 people have fled to neighboring nations.