Up to 10 people were killed when troops of the new regime in the Central African Republic battled fighters claiming loyalty to toppled President Francois Bozize, an army source said Monday.

The fighting broke out soon after 11:00 am (10:00 GMT) on Sunday on the northern edge of the town of Bossangoa "where heavy and light arms fire was heard ... between elements of (the ruling) Seleka and men claiming allegiance to the former president," the source told AFP, asking not to be named.

Aid workers who carried out an emergency mission to the north of strife-torn Central African Republic found villages abandoned and burned, and evidence of widespread rights abuses, the U.N. refugee agency said Friday.

"The UNHCR team confirmed widespread lawlessness in the region. Local people spoke of physical assaults, extortion, looting, arbitrary arrest and torture by armed men," said Melissa Fleming, spokeswoman for the U.N. High Commissioner for Refugees.

Thousands of people have fled violence in the Central African Republic in recent days, with as many as 6,000 temporarily taking refuge at the Bangui airport, the United Nations said Thursday.

"Over the past 10 days arbitrary arrests, detention, torture, extortion, armed robberies, physical violence, restriction of movement, lootings and attacks on civilians have displaced thousands of people," the U.N.'s refugee agency said in a statement.

French President Francois Hollande on Tuesday called on the United Nations and African Union to "take charge of the situation" in the violence-wracked Central African Republic.

The former French colony has been beset by reports of widespread rape, recruitment of child soldiers, weapons proliferation, huge population displacement and severe malnutrition since a coup in March.

At least 11 people were killed and 35 injured in clashes that erupted when the new Central African Republic government tried to disarm supporters of ousted leader Francois Bozize, hospital sources said Wednesday.

Six bodies were taken to the Amitie hospital in the capital Bangui and five to another community hospital, the sources told Agence France Presse.

Former rebel leader Michel Djotodia swore in as president of the Central African Republic on Sunday, five months after seizing power in the violence-wracked country.

The former French colony's sixth president is tasked with restoring security in the impoverished state and steering the nation through a transition period leading to fresh polls within 18 months.

The U.N. Security Council warned Wednesday that turmoil in the Central African Republic poses a "serious threat" to the country and the region, and urged new measures to restore stability.

A unanimous declaration of the 15 council members did not specify what these new options could be, but a recent report by U.N. Secretary General Ban Ki-moon recommended sanctions against officials from the Seleka coalition suspected of committing atrocities.

Top U.N. officials called on the international community Wednesday to act to keep crisis-torn Central African Republic from becoming a "failed state."

Speaking before the U.N. Security Council, the officials called on the body to support the African Union's efforts to restore order in the country, plagued by insecurity and humanitarian crisis.

Central African Republic's interim leader Michel Djotodia promised Tuesday to fight against the spread of weapons in the country, still suffering the aftermath of a coup earlier this year.

In an address to the nation on the 53rd anniversary of independence from France, Djotodia said the government had "taken measures to restore security".

The deposed president of the Central African Republic, Francois Bozize, has surfaced in France, where he told a radio station on Saturday that he would seek to return to power "if the opportunity presents itself".

Bozize, 66, fled the Central African Republic after the Seleka rebel coalition seized power on March 24 in the latest coup to hit the chronically unstable nation.