"The department recommends you avoid all travel to the city of Goma and the province of North Kivu," it said in a travel advisory. "Armed groups, bandits, and elements of the Congolese military remain security concerns in eastern DRC."
The March 23 Movement rebelled against the government DRC, accusing it of backing out of earlier peace agreements.
M23 seized control briefly over parts of North Kivu province last year. The movement last week fired twice on U.N. helicopters patrolling the region.
The State Department said armed groups like M23, operating in the eastern provinces, "are known to pillage, steal vehicles, kidnap, rape, kill, and carry out military or paramilitary operations in which civilians are indiscriminately targeted."
A U.N. mission in DRC is mandated to use force. The U.N. Organization Stabilization Mission in the DR Congo said Monday the arrival of troops from Malawi meant a so-called intervention brigade was at its full capacity of around 3,000 troops.
Former U.S. Sen. Russ Feingold, D-Wis., is serving as a regional special envoy to multilateral peace talks in neighboring Uganda.
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