A police officer was killed in DR Congo on Saturday as violence broke out after the crushing defeat of new President Felix Tshisekedi's party in the previous day's senate election.
Separately, presidential pardons from Tshisekedi released an opposition leader and a rights activist jailed during the presidency of Joseph Kabila.
Tshisekedi was sworn in on January 24 after a bitterly disputed election mired by fraud allegations, replacing Kabila who yielded power after 18 turbulent years at the helm of sub-Saharan Africa's biggest country.
But Kabila has retained significant influence as his Common Front for Congo (FCC) coalition wields overwhelming control of the lower house of parliament.
The pro-Kabila FCC extended its parliamentary dominance on Friday when it won "a very large majority of over two-thirds" of the country's more than 100 senate seats, the FCC said in a statement.
The size of the majority means the FCC will be able to make changes to the country's constitution or pursue legal proceedings against the current head of state.
Locally elected politicians in the country's provincial assemblies elect the senators in each region and some of them have been accused of having sold their votes.
Tshisekedi's UDPS, the Democratic Republic of Congo's largest and oldest opposition party, did not win a single senate seat in the central Kasai Oriental province, of which Mbuji-Mayi is the capital.
A policeman was killed in Mbuji-Mayi in the resulting violence, according to several sources.
Governor Alphonse Ngoyi Kasanji, who was elected as an FCC senator, said that "UDPS fighters this morning conducted punitive expeditions in the residence of some provincial deputies".
"They looted, destroyed and torched houses and vehicles. FCC MP Felicita Ngalula lost all her possessions. Her bodyguard was killed", he tweeted.
Civil society member Jimmy Bashile also said "angry UDPS fighters" had raided Ngalula's home.
"They arrived and ransacked everything. A police officer guarding her was killed," Bashile told AFP.
The police confirmed the death of one of their officers.
The UDPS also held protests on Friday night and Saturday in the capital Kinshasa, where the party also failed to win a single senate seat despite having 12 MPs in the provincial assembly.
Tshisekedi won a surprise victory in the presidential election held on December 30 after three postponements, beating opposition leader Martin Fayulu, whom pre-vote polls had predicted would prevail.
Fayulu says the result was a stitch-up between Tshisekedi and Kabila.
Nearly two months after his inauguration, Tshisekedi has been unable to push through his choice of prime minister as his party only garnered 32 seats out of 500 in the National Assembly.
Kabila, who as a former president has become a senator for life, meanwhile gathered the leaders of the FCC coalition's 18 member parties at his farm last month and pressed them to sign a loyalty pledge.
After his election, Tshisekedi pledged to release political prisoners from Kabila's reign.
The former leader of a minor opposition party, Franck Diongo, was released from prison in Kinshasa on Saturday.
He was arrested in December 2016 during protests against Kabila after the then president refused to step down when he reached the constitutional limit on his term in office.
On Friday, human rights activist Firmin Yangambi was also released after a decade in prison. "No spite or rancour," he said on Twitter. "It's time to save the Congo".