* Country riven by Muslim vs Christian violence
* In town of Boda, Muslims besieged
* Millions of people in need of aid, UN says
By Emmanuel Braun
BODA, Central African Republic, April 18 (Reuters) - In normal times, the rickety wooden bridges at each end of the red-dirt main street in Boda were gateways to shops and a bustling market in the diamond-mining town in Central African Republic.
Today, they mark the fine line between life and death for hundreds of Muslims living under siege, encircled by Christian 'anti-balaka' militia fighters bent on chasing out the country's Islamic population.
"We live in a prison," said Adou Kone, a tailor. "Everything is blocked, nothing comes in. It's very expensive to buy food ... Our life is at a critical stage."
Boda illustrates the chaos that has gripped Central African Republic since late 2012 when a battle for political power degenerated into clashes between Muslims and Christians that have forced about 1 million people from their homes.
If they stray beyond either bridge, Muslims in Boda say they would be killed, like thousands of other victims of tit-for-tat violence that continues despite the deployment of French and African peacekeepers.
French flags hang from some shacks and a handful of French armoured vehicles sporadically patrol the town, 115 km (70 miles) west of the capital Bangui. In the Muslim neighbourhood, a banner praises French troops - recognition that their plight would have been far worse without the deployment.
The crisis abruptly ended a proud history of Muslims living in harmony alongside the majority Christian population and has prompted warnings of genocide in the former French colony.
"We can wait for 10 years for them to leave - and if they don't leave, we will still be there, holding our positions," said Captain Dopani Firmin, the 'anti-balaka' chief in Boda, wearing a red Paris St Germain football shirt.
"We cannot accept to live together with Muslims, long-term," Firmin said. "It's our right to kill Muslims."
In a sign of the mounting sectarian violence, fighters from the Muslim Seleka rebels shot dead the priest of the northern town of Paoua, a church official in Bangui said on Friday. The attack came two days after Seleka gunmen briefly kidnapped the bishop of the nearby town of Bossangoa.
Virtually all Muslims have fled Bangui since Seleka, who seized power in March 2013, were forced to step aside in January. The United Nations has since reported a "cleansing" of Muslims from the country's west.
The United Nations Security Council this month authorised a 12,000-strong U.N. peacekeeping mission to be deployed in September, recognition that 6,000 peacekeepers from the African peacekeeping force (MISCA) and France's 2,000-strong Sangaris force had failed to stamp their authority on the country.
But the operation will take time to roll out and assaults on Muslims in Boda and elsewhere are taking a heavy toll.
"While we await the deployment on Sept. 15, it is essential that we reinforce MISCA and Sangaris, whose numbers are insufficient to stabilise this country," Abdou Dieng, U.N. Humanitarian Coordinator in CAR, told a news conference.
The United Nations says over half the population of 4.5 million people needs humanitarian aid but donors have provided less than 30 percent of the $550 million needed for emergency relief. Dieng said attacks on aid workers outside Bangui had also complicated the delivery of aid, amid fears the impending rainy season would worsen disease and malnutrition.
Adam Moussa, a health worker operating out of an office that used to house gold and diamond traders in Boda, said several weeks ago four people a day were dying from malnutrition but that rate fell to one death every two days after aid from the U.N. World Food Programme started reaching the Muslim community.
"I go to visit ... the children who suffer from malnutrition, particularly severe malnutrition, and we find many of them, more than 200 to 300," Moussa said.
Refugees are pouring over the border into neighbouring Cameroon at an average of 10,000 every week. "They arrive in poor health and with machete and gunshot wounds," OCHA said.
"New arrivals have been forced to walk through the bush for two to three months before reaching the border due to roadblocks set up by armed militias," it said in a report on Thursday.
The U.N. refugee agency warned this week that the conflict was getting neither the attention nor the aid needed to save lives, and the operation risked going broke.
While they have failed to restore order, the African peacekeeping mission, MISCA, and the French force, Sangaris, are escorting Muslims to safety, mostly in neighbouring Chad.
"If the Muslims want to leave, MISCA and Sangaris can escort them. There's no problem ... we won't kill them," said Simbona Guy Copain, a spokesman for the Christian community in Boda. "All that we want is their departure."
(Additional reporting by Crispin Dembassa-Kette; Writing by David Lewis; Editing by Daniel Flynn, Robin Pomeroy and Eric Walsh)