M23 denies Human Rights Watch findings linking it to massacres in eastern Congo, as rights groups cite mass killings and the U.S. urges U.N. action.

The Rwanda-backed rebel group M23 has denied involvement in recent massacres in eastern Congo. A report by Human Rights Watch, released Wednesday, accused M23 of killing over 140 civilians.

The main rebel group in eastern Democratic Republic of Congo, the M23, has walked away from peace talks with the government, saying it will not return unless the authorities adhere to a previous ceasefire deal.