Soldiers sealed part of Congo's second city and carried out mass arrests of young men on Thursday, residents said, as talks to defuse the country's explosive political crisis continued.
Protests and deadly clashes have erupted in the Democratic Republic of Congo over President Joseph Kabila's refusal to step down at the end of his mandate on December 20.
The army sealed off the Matshipisha-Gbadolite neighbourhood of Lubumbashi from 5 am (0300 GMT), five residents of the city told AFP. The operation was concluded by early afternoon, said the police commander in Haut-Katanga province, Jean-Bosco Galenga.
On Wednesday the region's governor Jean-Claude Kazembe was forced to flee as stones were thrown at him when he tried to visit Matshipisha on a "peace march" aimed at demonstrating that the authorities were in control there following deadly violence on Tuesday.
"The objective of sealing off (the area) was to retrieve three weapons stolen from police during clashes on 20 and 22 December (when) two police stations were looted," said Galenga.
The weapons were all successfully located, he added.
Police said a total of 20 people were killed Tuesday in clashes in the capital Kinshasa, Lubumbashi in the southeast, and Matadi and Boma in the west.
Galenga said six of the deaths were in Matshipisha, revising down an earlier death toll. Forty-seven people were also injured in the district.
Human Rights Watch has put the total death toll at 34, increasing an earlier estimate.
Matshipisha residents said that the army sealed off the district, going house-to-house, searching and arresting young men and teenagers.
"They put them in trucks to take them off in an unknown direction," said one resident, adding that two adolescents and a young man were arrested in his area.
"I saw three trucks filled with young people," said another.
Several dozen people, representing families of those detained, demonstrated outside the Lubumbashi headquarters of the UN's MONUSCO force to protest against the "arbitrary arrests". They were cleared by Congolese police around 11:30 am without incident.
Lubumbashi, the capital of Haut-Katanga, is the fiefdom of an opposition leader in exile, Moise Katumbi.
Talks to end the political crisis headed by the bishops' conference CENCO resumed on Wednesday after breaking up at the weekend without a breakthrough.
CENCO chairman Archbishop Marcel Utembi appealed for a deal by Christmas. CENCO has also called for an independent investigation into the violence that greeted the end of Kabila's mandate.
The conference said it hoped to hold a meeting at 5:00 pm (1600 GMT) to give an update on how the talks are progressing.
The mainstream opposition headed by 84-year-old Etienne Tshisekedi has called for "peaceful resistance" from the country's 70 million people, pinning its hopes on a deal at the negotiating table.
But in what Kabila's opponents dubbed a provocation, a new government was announced overnight Monday.
In separate development, 17 people were killed in clashes between Congolese police and members of a cult that believes the end of Kabila's mandate will usher in the apocalypse, a regional governor said Thursday.
Bienvenu Esimba, governor of northwestern Mongala province, said the clashes broke out Wednesday in the provincial capital Lisala when members of the sect burned dozens of houses and attacked a market before launching an assault on local electoral commission offices.
Kinshasa was calm on Wednesday although security forces were still out in force, manning roadblock checkpoints that were erected overnight.
Thierry Vircoulon, a central Africa specialist at France's Sciences Po university, said that the scope for protest in Kinshasa had been "locked down" and that opposition might now shift to areas outside the capital "and take the form of regional rebellions".
Congo has never witnessed a democratic transfer of power following polls since independence from Belgium in 1960.
The president has been in office since his father Laurent Kabila's assassination in 2001. He was elected in 2006, and again in 2011.
Two decades ago, the country collapsed into the deadliest conflict in modern African history. Its two wars in the late 1990s and early 2000s dragged in at least six African armies and left more than three million dead.