The attack comes after five international aid agencies temporarily suspended their operations in northern Central African Republic last week due to attacks on humanitarian workers by armed groups.
Four United Nations peacekeepers in Central African Republic have been killed and eight wounded following an attack on their convoy late on Monday by militants in the southeast of the country, the UN mission (MINUSCA) said on Tuesday.
One peacekeeper, from Cambodia, was killed by gunfire during Monday's attack near the town of Bangassou, about 730 kilometres (450 miles) east of the capital Bangui, MINUSCA said in a statement.
Three other peacekeepers were found dead on Tuesday, having gone missing during the attack, according to the mission.
One peacekeeper remains missing.
Eight anti-balaka militants were also killed and several injured during Monday's attack.
A UN helicopter and peacekeepers were sent to secure the area and search for the missing, while the injured peacekeepers were evacuated by plane to a hospital in Bangui, MINUSCA said.
"We will keep doing everything we can to find our missing colleague," MINUSCA spokesman Herve Verhoosel said.
The attack came after five international aid agencies temporarily suspended their operations in northern Central African Republic last week because of attacks on humanitarian workers by armed groups.
Central African Republic is one of the most dangerous countries in the world for aid agencies, the UN Office for the Coordination of Humanitarian Affairs (OCHA) said last week, with at least 33 attacks on aid workers in the first quarter of 2017.
The country has been plagued by inter-religious violence since 2013, when mainly Muslim Seleka fighters seized power, prompting reprisals from the Anti-balaka militia.
The Seleka and other groups have since splintered, prompting further violence despite the election in March 2016 of President Faustin-Archange Touadera, which raised hopes of reconciliation.
The UN mission has 13,000 peacekeepers on the ground, but some civilians complain it does not do enough to protect them against dozens of armed groups.
Around 425,000 people have been uprooted by the fighting within Central African Republic, some 465,000 have fled to neighbouring countries, and more than 2.2 million, nearly half the population, need humanitarian aid, according to OCHA.