GOMA, Congo (AP) — At least 50 people were killed in weekend attacks in conflict-battered east, authorities said Saturday. The government traded blame with Rwanda-backed rebels over who was responsible for the violence that quickly escalated the conflict in the region.

The renewed violence that residents reported in and around the region’s largest city of Goma — which the control — was the biggest threat yet to by both the Gulf Arab state of Qatar and African nations in the conflict that has raised fears of regional warfare.

Goma resident Amboma Safari recounted how his family of four spent the night under their bed as they heard gunfire and bomb blasts through Friday night. “We saw corpses of soldiers, but we don’t know which group they are from,” Safari said.

The decades-long , when the rebels made an unprecedented advance and seized the strategic eastern Congolese city of Goma, followed by the town of in February. The latest fighting has killed some 3,000 people and worsened what was already one of , with around 7 million people displaced.

At least 52 people were killed between Friday and Saturday, including a person shot dead at Goma’s Kyeshero Hospital, Congo’s Ministry of Interior said in a statement that blamed the attack on M23.

M23 spokesperson Lawrence Kanyuka issued a statement blaming Congolese forces and their allies for the attacks. Kanyuka said Congo’s joint operations with local militias and southern African troops “directly threaten the stability and security of civilians” in the region.

The group said it has been compelled to “reconsider its position to prioritize the security” of the people in the area, suggesting the crisis could worsen.

Christian Kalamo, a civil society leader in the North Kivu province that includes Goma, said at least one body was seen on the streets on Saturday.

“It is difficult to know if it is the Wazalendo, the FARDC (Congolese forces) or the M23″ that carried out the attacks, Kalamo said. “Now, we don’t know what will happen, and we live with fear in our stomachs, thinking that the war will resume.”