More than a dozen people were killed in clashes in Burundi last Monday and Tuesday, in the latest violence linked to the disputed third term of President Pierre Nkurunziza, the police have said.
The police said the situation had sparked concern by the United Nations Security Council.
Nkurunziza triggered weeks of protests and a failed coup when he announced in April he would seek a third term, plunging Burundi into its worst crisis since a civil war ended in 2005.
He won the disputed vote in July but tensions have remained high, and at least 198 people have been killed since April.
The UN Security Council last Wednesday expressed "deep concern about the growing insecurity and the continued rise in violence." In a French-drafted statement, it strongly condemned human rights abuses and unlawful violence by security forces and militias and pledged to seek accountability for such acts.
Activists and officials have reported a number of apparently t