Three local administrators have been killed in several parts of Burundi since Friday, officials said, in the latest case of deadly violence that has hit the small African nation.
Burundi has been in a cycle of violence since April 2015 when President Pierre Nkurunziza won a disputed election following his decision to seek a third term, despite a constitutional two-term limit.
More than 400 people have been killed and about 3,500 have been arrested in Burundi, under the government crackdown, since last year.
Gad Niyukuri, governor of Makamba Province, said in the latest incident unidentified gunmen killed the head of a village in Kibago District in the province on Tuesday night.
"The victim was attacked at his home around 10pm by unidentified gunmen," he told Reuters.
In another incident on Tuesday, gunmen killed another village head in Mugamba District in Bururi Province, 70 km away from the capital Bujumbura, according to a resident in the province.
"Gunmen came around 7pm last night fired several rounds of bullets at the victim's home killing on spot the head of village only," a resident who only introduced himself as Antoine said.
"Another local elected official was also killed last Friday by unidentified gunmen."
Although no group has claimed responsibility for the attacks, the government says there are now three rebel groups perpetrating violence, including two made up of deserters.
However, the opposition accuses the government troops of permissive arrests, disappearances and extra-judicial killings.
According to statistics by the United Nations refugee agency UNHCR, as of early March, 250,473 Burundians have fled the country, fearing possible genocide. They were registered as refugees in neighbouring countries including Democratic Republic of the Congo, Rwanda, Tanzania, Uganda and Zambia.
On Monday, The European Union suspended its direct financial support to the government of Burundi after the bloc concluded that it had finished peace talks with Burundian government to find a political solution for the conflict.
From 1993 to 2005 Burundi was under a civil war in which approximately 300,000 people died due to conflict between rebels from the country's majority Hutu population and an army dominated by the Tutsi minority.
The African Union and United Nations have warned in the past of possible tribal war and genocide in Burundi.