Bangui - The United Nations peacekeeping mission in Central African Republic is requesting about 750 more troops to help fill a "security vacuum" worsened by the withdrawal of US special forces as violence surges again, according to a confidential cable obtained by The Associated Press.The additional troops are needed in the southeast after the withdrawal this year of U.S. and Ugandan troops hunting the Lord's Resistance Army rebels, according to the message from mission head Parfait Onanga-Anyanga to the UN's head of peacekeeping operations in New York.Hundreds of people have been killed since May and more than half a million people have been displaced as largely sectarian violence moves into parts of Central African Republic that were spared the worst of the fighting that began in 2013. International observers warn that the country is approaching the levels of violence seen at the height of the conflict in 2014.The UN Secretary General Antonio Guterres on Wednesday said he wanted to "shine a spotlight on an under-reported emergency" in Central African Republic, which has seen a 37 percent increase in refugees and displaced people in the past three months.Increased attacks on civilians Rebel groups control an estimated 70 percent of the country, according to international human rights organisations. The UN mission has acknowledged that its authorised force of 10 750 military personnel and 2,080 police is not enough in the country roughly the size of Texas.The request for more troops would increase the total of uniformed peacekeepers to about 13,500."It's pretty clear that the mission, with its current capacity, is overstretched," said Human Rights Watch researcher Lewis Mudge. "They simply don't have the means to address the increased attacks on civilians."The fighting is mostly between predominantly Muslim ex-Seleka rebels and majority Christian anti-Balaka fighters over resources and trade routes in the countryside.The existence of the Lord's Resistance Army rebel group in the region is also a concern. The US and Ugandan militaries in pulling out of the hunt for the LRA said the group had largely been neutralized. However, leader Joseph Kony, who is wanted by the International Criminal Court for alleged war crimes, remains one of Africa's most-wanted fugitives. The UN has reported kidnappings by the LRA in the region since the pullout.In his cable, Onanga-Anyanga wrote that "new actors are emerging to fill the security vacuum (in the southeast), creating upheaval in a once relatively calm region." Those include offshoots of the ex-Seleka and anti-Balaka fighters.Peacekeeping budgets The UN peacekeeping mission needs an "urgent increase in military capabilities given the deteriorating security situation and escalating violence against civilians, humanitarians and peacekeepers," said Evan Cinq-Mars?, the UN advocate and policy adviser at the non-profit Center for Civilians in Conflict.But any request for more resources for the UN mission is challenged by pressure from the Trump administration to cut peacekeeping budgets, even though the US ambassador to the UN, Nikki Haley, met with Central African Republic President Faustin Touadera in March and reaffirmed US support for the country.The UN peacekeeping mission did not comment.The additional peacekeepers, if granted, also may be used to push out the ex-Seleka rebel group Popular Front for the Renaissance of Central African Republic. Onanga-Anyanga's cable said the mission's force commander is "confident the armed groups can be ousted from Bria" town in the southeast.The UN peacekeepers earlier this year forced the ex-Seleka rebel group Union for the Peace in Central African Republic out of the central mining town of Bambari.Mudge, who recently visited Bambari, said the town is doing better now with the peacekeepers and state security forces back in control."Efforts to oust (rebels) from major towns, as long as there are sufficient blue helmets to maintain peace, may increase stability in the east," Mudge said, referring to the peacekeepers.