Rwandan soldiers shot dead a Congolese soldier who crossed the border and shot at security forces on Friday, triggering a brief exchange of fire between the two sides, Rwanda's defence ministry said.
Already strained relations between the central African neighbours have deteriorated sharply since the M23 rebel group launched a fresh offensive in eastern Congo in March last year, displacing over 600,000 people since.
Congo accuses Rwanda of backing the Tutsi-led group. The United Nations, the United States, France and other international powers have made similar allegations.
