Central African Republic President Faustin Archange Touadera declared three days of national mourning as UN Secretary General Antonio Guterres called for calm in the troubled nation.
Fresh violence in the capital Bangui on May 1, 2018 claimed several lives, including that of a religious leader.
President Touadera said in a statement late Wednesday that the flags would be raised at half-mast on all public buildings during the mourning period from Thursday.
He, however, pointed out that the of mourning were not public holidays.
Mr Guterres condemned Tuesday's attacks, which also left about 170 people wounded, and "urges all actors to cease violence and work together to bring peace and stability to the country," his deputy spokesman Farhan Haq said in a statement.
"The Secretary-General calls for calm and urges the Central African Republic authorities to investigate these repeated attacks and quickly bring those responsible to justice."
According to the UN Multidimensional Integrated Stabilisation Mission in CAR (MINUSCA), Tuesday’s violence started when security forces arrested a member of an armed group. In retaliation, the criminal group targeted a church, a mosque and medical facilities in Bangui’s predominantly Muslim PK5 and Fatima neighbourhoods.
MINUSCA condemned the attacks and emphasised that they violated national and international laws.
“The Mission emphasises that these acts are of criminal nature and only serve to destabilise the country and its institutions,” MINUSCA said in a statement.
It called on the population of Bangui and the country in general to avoid any escalation of violence.
The UN peacekeeping mission said it had deployed reinforced patrols to secure key locations in Bangui.
One of the world's poorest and most unstable countries, the CAR spiralled into bloodshed after long-time leader Francois Bozize was overthrown in 2013 by a mainly Muslim rebel alliance called the Seleka.
President Touadera governs with the support of a large UN peacekeeping operation, yet can only claim to control a fraction of the country.
(Additional reporting by AFP)