Congo police made a pre-dawn raid on a separatist group in Kinshasa on Tuesday, killing four people but failing to arrest their leader, a self-styled religious prophet, witnesses and group members said.
Dozens of armed police stormed the home of Ne Muanda Nsemi, leader of Bundu dia Kongo, a religious cult that seeks to revive the pre-colonial Kongo kingdom that flourished for centuries around the mouth of the Congo river.
Police have clashed with BDK members several times in the past few weeks in their western heartland of Kongo Central province, but the spread of violence to the capital, hundreds of kilometres away, is a serious escalation.
It also adds to wider tensions across Congo since President Joseph Kabila refused to step down after his mandate expired in December, raising fears of a slide back into civil war.
Spokesman Pierre Mwanamputu said Muanda Nsemi's supporters had participated in an "armed insurrectional movement" in Kinshasa on Monday.
Members of the BDK said the four fatalities were due to police preventing the wounded getting swift medical attention.
Residents think the raid may have been provoked by a video circulating on social media in which Muanda Nsemi appears to threaten Kabila.