DAKAR, Senegal (AP) — The U.S. government on Tuesday sanctioned an armed group accused of illicit trading in minerals in eastern Congo as Washington tries to spearhead peace efforts there while pushing for U.S. access to the region’s minerals.

The United States has sanctioned an armed group accused of illicit mining in the Democratic Republic of the Congo (DRC), as both the army and the Rwandan-backed M23 rebel group traded accusations of violating a recently reached US-mediated ceasefire deal by attacking each other’s positions.

The US sanctioned an armed group and two Hong Kong-based firms allegedly linked to violence and illegal mining in the Democratic Republic of Congo, part of what officials said was an effort to combat the trade of conflict minerals from the region.