AT LEAST 12 people including children and a pregnant woman have been killed by Christian vigilantes in the Central African Republic, a military source said.

A pregnant woman was disembowelled and 10 children slashed with machetes in the vicious attack against members of the Peuhl Muslim minority, which took place about 95 kilometres north of the capital Bangui.

The attack comes with the UN Security Council set to vote on creating a large peacekeeping force for the impoverished country, where the transitional government has lost control since rebels forced the president to flee in March.

"The assailants were seen not far from the camp and they returned in the night to attack the herdsmen who were there with just knives,'' a military source said.

"Among the victims were children and a disembowelled pregnant woman. Some managed to escape and there are more than 10 wounded who have been transferred to Bangui,'' the source added.

A healthcare worker said 10 very young children were hospitalised with machete wounds to the head and limbs.

The father of one of the injured children, who lost his wife and another child in the attack, recounted the ordeal from his son's hospital bedside in Bangui.

Shots were fired, but the assailants mostly struck with machetes, added the man, who refused to give his name for fear of reprisals.

"We regularly see people with machete wounds, but not so many at one time, this has never been seen,'' a nurse said.

The Peuhl people are traditionally pastoralist, and make up a minority in the impoverished, landlocked nation of 4.5 million people which was plunged into chaos after a March coup by the mostly Muslim Seleka rebels.

Rebel leader Michel Djotodia has since become the country's first Muslim president, and has formally disbanded the Seleka.

But rights groups say the motley crew of ex-rebels have taken to looting and burning villages across the mineral-rich country of 4.5 million people.

Locals in the majority Christian country have responded by forming vigilante groups known as "anti-balaka'' (anti-machete).

They are mostly located in the northeast of the country, where since September, at least 150 people have been killed and tens of thousands displaced in escalating violence.

The clashes have taken on a religious undertone, raising fears of sectarian massacres, prompting the United Nations, the United States and former colonial ruler France to warn that the situation could degenerate into genocide.

France last week began deploying troops to the country and Paris is Saturday holding a mini-summit on the crisis, with 40 African leaders and UN chief Ban Ki-moon due to attend.

The Security Council is expected on Thursday to adopt a resolution aimed at restoring order to the country.

The text would give a UN mandate to the African Union force already on the ground to "stabilise'' the country and protect its civilians.

The beleaguered 2,500-strong African-led force known as MISCA is to increase to 3,600 this month. Ban said in a recent report that 6,000-9,000 troops would be needed if the UN steps in.

Lying in the heart of Africa, CAR has struggled with a series of coups and rebel uprisings since gaining its independence in 1960.