The 2015 Clinton Correctional Facility escape was a high-profile jailbreak in which two convicted murderers, Richard Matt and David Sweat, escaped from a maximum-security prison in Dannemora, New York. On June 6, 2015, the inmates used power tools to cut through the backs of their cells, accessed a network of tunnels, and emerged through a manhole cover approximately 500 feet outside the prison walls. Their escape was facilitated by Joyce Mitchell, a prison seamstress who smuggled in tools and had planned to assist them in their getaway.