The Globe and Mail reports in its Wednesday edition that Rwanda-backed M23 militia executed at least 21 civilians, and probably many more, in a two-day killing spree that began within weeks of its capture of the Congolese city of Goma in January, a new report says. The Globe's Geoffrey York writes that the Human Rights Watch report is the latest in a series of disturbing allegations of mass arrests, killings and torture by M23 in the territories it has seized across a vast swath of the eastern region of the Democratic Republic of the Congo in recent months. By directly supporting the M23 rebels, Rwanda may be complicit in war crimes in the region, Human Rights Watch said. In defiance of U.S.-sponsored peace talks, M23 has continued to capture new towns and villages across eastern Congo in the past several weeks. It shows no signs of ending a prolonged offensive that has triggered a humanitarian catastrophe, causing thousands of deaths and displacing millions of people. (In March, the Alphamin tin mine in eastern Congo was shut and its employees evacuated after the rebels advanced close to the town. Next month, the U.S. government obtained help from Rwanda to secure a rebel retreat and allow Alphamin to reopen the mine.)