The death toll of militiamen killed in rival group fighting in the Central African Republic at the weekend has risen to 38, according to an internal United Nations report seen by AFP on Monday. The UN Mission in Central Africa (Minusca) initially put the death toll at 23. The two armed groups had signed a peace deal in February. Fierce clashes between militias in recent months have raised concerns about whether the peace accord aimed at ending years of violence in CAR will hold.The country's president, Faustin-Archange Touadera, this month told AFP that the agreement was "quite strong" -- but Minusca on Saturday said fighting had broken out in Birao, a city close to the Sudanese border.The clashes were between the Popular Front for the Renaissance of the Central African Republic (FPRC) and the Movement of Central African Freedom Fighters for Justice (MLCJ).The rival militias also fought in the city earlier this month."The situation remains tense but there is no more fighting," Minusca spokesperson Vladimir Monteiro said."A Minusca Blue Helmet was also slightly wounded," he added, without specifying the nationality. A Zambian contingent of the multinational force is stationed in the area.The peace accord with 14 militias vying for control of the CAR's gold, diamond and other resources came after years of conflict following the ousting of former president Francois Bozize in 2013.Thousands of people have been killed and about a fifth of the 4.5 million population has been displaced in the last six years.Touadera has been struggling to prove he can convince the militias, which collectively control more than three-quarters of the territory, to lay down their arms.