Several people were killed and wounded in shootings at two police headquarters in Vietnam's Central Highlands on Sunday, authorities said.

Six people were arrested in connection with the shootings in Cu Kuin district of Dak Lak province, according to the ministry of public security's website.

Investigators were searching for more suspects, it said.

The attacks on the police headquarters of both Ea Tieu and Ea Ktur communes occurred in the early hours of Sunday, according to the site.

It said a number of people, including police, local officials and civilians were killed and wounded but did not provide exact figures.

Police could not be reached immediately be reached for comment.

The Central Highlands, home to a number of ethnic minorities, is considered a sensitive area for Vietnam's authoritarian government and has long been a hotbed of discontent over issues that include land rights.

Some tribes in the area  -- collectively known as Montagnards -- sided with the US-backed south during Vietnam's decades-long war. Some are calling for more autonomy, while others abroad advocate independence for the region.

Several state media outlets withdrew their reports about the incident earlier on Sunday before republishing them hours later.

Gun violence is extremely uncommon in Vietnam, where it is illegal for citizens to own firearms and the black market for weapons is limited.

Four people were shot dead at an illegal cockfighting betting ring on the outskirts of Ho Chi Minh city in January 2020.

In another rare shooting in 2016, two senior officials in northern Yen Bai province were killed by a colleague at their office before the gunman shot himself.