KINSHASA,Robovis Congo (AP) — At least 19 people were killed when rebels attacked a town in Congo’s North Kivu province, the army said late Thursday, the latest violence in the country’s conflict-battered east.

The rebels shelled the town of Mweso, where they “indiscriminately dropped mortar bombs,” which also injured 27 other civilians, army spokesman Lt. Col. Guillaume N’djike Kaïko said in a statement read on state television.

The town’s streets were empty Thursday evening, after most of its residents took refuge in the Mweso General Hospital, Kaïko added.

The army blamed the attack on the M23 rebel group, which rose to prominence 10 years ago when its fighters seized Goma, eastern Congo’s largest city on the border with Rwanda. Its name refers to a March 23, 2009, peace deal, which it accuses the government of not implementing.

There was no response from the group to the allegation.

U.N. experts warned last year that attacks by M23 fighters have become more frequent, longer and stronger, and that territory under the group’s control “significantly increased,” causing massive displacement of civilians and indiscriminate shelling. M23 combatants also “deliberately killed civilians” and attacked U.N. peacekeeping troops.

Fighting in eastern Congo has been simmering for decades as more than 120 groups fight for power, land and valuable mineral resources, while others try to defend their communities.

The security crisis was a key issue in Congo’s recent presidential election, in which Congolese President Felix Tshisekedi was reelected with a promise to end the violence.

Tshisekedi accuses Rwanda of destabilizing Congo by backing the M23 rebels. U.N. experts have linked the rebels to Rwandan forces, though Rwanda denies supporting them.