At least nine people, including seven children, were killed on Friday in a strike on a displacement camp in the easternCongolese city of Goma, a local official and a military spokesman said.
It was not immediately clear what kind of explosive device was used or who was responsible for the attack.
A two-year offensive by the Rwanda-backed rebel group M23 has moved closer to Goma in recent months, prompting thousands to seek refuge in the city from surrounding areas.
President Felix Tshisekedi, who has been abroad for several weeks, decided to return toCongoover the weekend following the attack, the presidency said.
Dedesi Mitima, the head of the Lac Vert district where the incident occurred, told Reuters he had seen the bodies of seven children and two men at the camp.
Several other people were wounded and the death toll could rise further, Mitima added.
A civil society leader in Goma, Marrion Ngavho, said three bombs fell on the camp.
"We have already registered 13 dead, including women and children. There are also around 30 people wounded," he said.
Lieutenant-Colonel Guillaume Njike Kaiko, a spokesman for the Democratic Republic ofCongo's (DRC) army in the region, said the strike had come in retaliation for earlier DRC attacks on Rwandan army positions which he said had destroyed arms and ammunition. He gave no details about the attack on the camp.
Congo's government spokesperson Patrick Muyaya, in a message on X, also blamed the Tutsi-led M23 for Friday's attack.
Opposition leaders condemned the attack on X, calling on the international community to backCongoand act against Rwanda's military involvement in the country.
TheCongolese government, U.N. officials and Western powers have repeatedly accused Rwanda of providing support for the M23. Rwanda denies this.
An M23 leader, Bertrand Bisimwa, also writing on X, accused theCongolese authorities of deliberately attacking the camp in an attempt to "manipulate" the international community.
TheCongobranch of medical charity Doctors Without Borders (MSF) said it had to stop a distribution round and halt medical consultations on Friday morning because of rising insecurity.
MSFCongo"condemns the increasingly regular use of heavy artillery in the immediate proximity of displacement camps around Goma," it posted on X.
The United Nations' peacekeeping mission inCongo, MONUSCO, also condemned the bombing in a statement and called onCongolese authorities to prosecute perpetrators.
In February, a strike blasted a crater into the ground in the same Lac Vert neighbourhood. Nobody was hurt in that attack, but it underscored the seriousness of the threat to Goma, a strategic urban hub in the conflict-ridden eastern DRC.
Rwanda on Saturday denied U.S. accusations that its forces attacked a displaced persons' camp in eastern Democratic Republic of Congo (DRC) and instead blamed militias it said were supported by the Congolese military for the assault.
The U.S. strongly condemned Friday's attack which killed at least nine people, the U.S. State Department said in a statement.
The attack was mounted from positions held by the Rwandan Defense Forces (RDF) and the Rwanda-backed M23 rebel group, the U.S. statement said. The U.S. is "gravely concerned about the recent RDF and M23 expansion" in eastern Congo, it said.
Rwandan government spokesperson Yolande Makolo denied the RDF was behind the attack and instead blamed it on militias supported by the Congolese military.
"The RDF, a professional army, would never attack an IDP (displaced persons). Look to the lawless FDLR and Wazalendo supported by the FARDC (Congolese military) for this kind of atrocity," she said in a post on X.