The statement by MINUSCA says the rebel coalition launched an attack on the peripheries of the capital, Bangui, on Wednesday morning.
Armed militias are being blamed for extensive abuses against the local population, including extorting money from merchants and attacking civilians, according to MINUSCA.
It said that the attack was repulsed by the blue helmets, in conjunction with the Central African armed forces, part of the statement said.
The Special Representative of the Secretary-General of the United Nations in the Central African Republic and Head of MINUSCA, Mankeur Ndiaye, strongly condemned the attacks by the anti-Balaka, UPC, 3R and MPC coalition armed groups and their political allies, notably former CAR President François Bozize.
"The mission holds them responsible for the consequences of this violence on the civilian population and stresses that attacks against peacekeepers can be considered as war crimes and prosecuted" the statement said.
Earlier last month Rwanda deployed special force protection troops to the Central African Republic, under an existing bilateral agreement on defense.
The deployment is in response "to the targeting of the Rwanda Defence Force (RDF) contingent under the UN Peacekeeping force by rebels supported by François Bozize".
On many occasions, Rwandan troops in CAR have been targeted by armed groups in that country.
Currently, the Rwanda Defence Force has been one of the largest troop contributor to the United Nations Multidimensional Integrated Stabilization Mission in the Central African Republic (MINUSCA) since 2014.