Gunmen executed nine people in Burundi's capital hours before police launched house-to-house searches for weapons on Sunday, amid international fears of fresh bloodletting in the central African nation.
Hundreds of police and soldiers ringed the opposition flashpoint Mutakura district of the capital Bujumbura early Sunday to start a widely feared crackdown on "enemies of the nation."
Residents said security forces carried out house-to-house searches.
City mayor Freddy Mbonimpa said police were searching for "hidden weapons," insisting the raids were being "done professionally, because the police are using weapon detectors."
The mayor said seven people were killed in an "execution" attack on a bar on Saturday night, adding that a probe had been launched to track the "assassins." Two others later died of their wounds.
Witnesses said attackers stormed into the bar, forcing those drinking outside to enter and lie on the ground before opening fire.
International alarm has grown as a government amnesty to hand in weapons ended with fears that it will trigger further violence, drawing warnings from the head of the UN, Washington and the world's only permanent war crimes court.
Police later displayed around a dozen rifles and grenades they said had been seized in the raids, which officials said would continue in coming days.
- 'Corpses litter the streets' -
Rwandan President Paul Kagame has accused Burundi's leaders of carrying out "massacres" on their people in his most critical speech yet of the crisis in the troubled neighbouring state.
"People die every day, corpses litter the streets... How can the leaders allow their population to be massacred from morning to night?" Kagame said, speaking in Kinyarwanda on Friday.
Relations between Rwanda and Burundi are tense, with Bujumbura accusing Kigali of backing those who oppose President Pierre Nkurunziza's controversial third term in office.
Burundi has been hit by waves of violence since Nkurunziza launched his successful bid to win a third term, with bodies found dumped in the streets on a nearly daily basis.
People in largely opposition areas have fled Bujumbura, leaving key districts that have seen some of the worst recent violence almost empty.
The security warnings have sparked intense fear.
"I was terrified, I understood that this time they would kill every last one of us," said Marie, a secretary in her forties who fled Mutakura on Saturday, taking her five children to a relative's house in a calmer part of the capital.
But apart from the bar attack, the city was otherwise reported to be largely calm, the mayor said.
At least 200 people have died in turmoil since April and 200,000 have fled the country, sparking fears that the violence could spiral into mass bloodletting.
"Inflammatory rhetoric deployed in recent days by some government officials and President Nkurunziza's planned security crackdown this weekend are increasing the risk of an outbreak of mass violence," the US said Saturday.
- 'No war or genocide' -
But the government dismissed the concerns, saying it wanted only to crush "terrorism" and comparing the fight to Somalia's struggle against Islamist Al-Shebab insurgents that Burundi is fighting as part of an internationally backed African Union force.
"There will be no war or genocide," presidential communications chief Willy Nyamitwe told AFP on Saturday.
"It is amazing to see that a government that wants to put an end to terrorism is criticised instead of being encouraged," he added.
The rising unrest has sparked fears Burundi could slide back into conflict after its 1993-2006 civil war, when some 300,000 people died as rebels from the majority Hutu people clashed with an army dominated by the minority Tutsis.
UN Secretary General Ban Ki-moon said Friday that the discovery of bodies -- "many apparently summarily executed" -- has become a "regular occurrence" in Burundi's capital Bujumbura.
Last week, the country's Senate president Reverien Ndikuriyo threatened to "pulverise" regime opponents who do not lay down arms before the Saturday deadline.
"Today, the police shoot in the legs... but when the day comes that we tell them to go to 'work', do not come crying to us," he said.
The loaded term "work" was a euphemism used in Rwanda during the 1994 genocide to describe the mass killings of at least 800,000 mainly Tutsi people by extremist Hutu militias.
Kagame said the violence in Burundi reminded him "a little" of the horrors of 1994 in Rwanda.
"They should learn from what happened here," Kagame said.