Hundreds of angry demonstrators on Wednesday laid the bodies of at least 16 people killed in clashes in Central African Republic’s capital in front of the mission headquarters of the United Nations, witnesses said.

U.N. peacekeepers and local security forces have battled armed groups in Bangui’s PK5 neighourhood - a Muslim enclave of the majority Christian city - since Sunday aiming to dismantle their bases there.

The demonstrators, who blame U.N. soldiers for firing on residents protesting against the operation in PK5, carried the bodies wrapped in cloth to the gates of mission, known as MINUSCA.

They shouted and carried improvised signs as armed peacekeepers stood before the entrance to the fortified compound.

“We, ourselves, no longer understand anything. Does their mission consist of shooting at civilians?” said one demonstrator, who gave his name only as Youssouf.

One Rwandan peacekeeper was killed and eight others were wounded in fighting on Tuesday.

The surge in violence coincides with a visit by Jean-Pierre Lacroix, the U.N.’s head of peacekeeping operations, to the country that has been mired in a cycle of ethnic and religious violence since 2013.

Atahirou Balla Dodo, the mayor of the Bangui district in which PK5 is located, told that a total of 21 people were killed in the clashes. Seventeen were brought to MINUSCA, while four others, including two women and two children, had remained at a mosque.

The bodies were later removed from MINUSCA by the local Red Cross.

Medical charity Medecins Sans Frontieres (MSF), which operates one of the main hospitals in Bangui, said it had treated more than 40 people for gunshot wounds on Tuesday.

MINUSCA officials were not immediately available on Wednesday to comment on the accusations that peacekeepers were responsible for the deaths.

Violence increased in Central African Republic after mainly Muslim Seleka rebels ousted president Francois Bozize in 2013, provoking retaliation killings by “anti-balaka” armed groups, drawn largely from Christian communities.

Self-styled Muslim self-defence groups sprang up in PK5, claiming to protect the Muslim civilians concentrated there against efforts to drive them out.

But MINUSCA now accuses them of extortion and violence against civilians and said it had launched the operation in PK5 at the request of the neighbourhood’s residents.

In a statement late on Tuesday MINUSCA said that Rwandan peacekeepers had come under attack.

“For four hours, the MINUSCA force had to push back heavily armed elements of criminal gangs who deliberately opened fire on the international forces, who fired back,” it said. “Any attack against (U.N. troops) can constitute a war crime.”