BANGUI (Reuters) - Machinegun and heavy weapons fire rang out in Central African Republic's capital Bangui overnight into Thursday morning, witnesses said, after days of escalating violence between the city's Christians and Muslims.
It was not immediately clear who was involved in the latest clashes in the country where thousands have died and more than a million have fled during two years of conflict.
A Reuters witness said he could hear mortar fire coming from the city's KM-5 neighbourhood and the streets emptied as people fled.
Thursday's fighting was the most serious crisis the country has faced in months, Human Rights Watch emergencies director Peter Bouckaert said on Twitter.
The former French colony, one of Africa's poorest despite reserves of gold and diamonds, was plunged into chaos when mostly Muslim Seleka rebels started attacking towns and grabbing territory before seizing power in March 2013.
Seleka's rule was marked by abuses that prompted a backlash from Christian militia known as anti-balaka. Tit-for-tat violence has continued despite the Seleka leader's resignation from the presidency in January.
The head of the local branch of the Red Cross, Pastor Antoine Mbao Bogo, said there had been a number of deaths in the latest fighting, but he had had to suspend operations to help the wounded and pick up dead bodies in the streets.
"We have been forced to do so because of the direct threat to our staff members," he said, declining to say who had made the threats.
An international aid worker told Reuters she had been told to stay at home.
"Clashes are going on in Castor and around that area," she said, referring to a part of Bangui. There were reports of anti-balaka militia stopping people in the streets and checking people's papers, she added.
The was no immediate comment from the government.
The U.N. mission in the country issued a statement late on Wednesday calling for dialogue between the various political actors. It condemned the deaths, injuries and acts of violence but gave no further details.
Most Muslims have fled the south of the country, creating a de facto partition. Some members of the Seleka leadership have pushed for this to be formalised.
(Reporting by Crispin Dembassa-Kette and Serge Leger Kokpakpa in Bangui; Additional reporting by Bate Felix and David Lewis in Dakar; Writing by David Lewis; Editing by Andrew Heavens)