December 1997—Career criminal Richard Matt and an accomplice kidnap, torture and murder William Rickerson, 76, a North Tonawanda businessman. Matt flees to Mexico.
March 1998—After killing a man in a Mexico strip club, Matt is convicted and sent to a Mexican prison, where he serves nine years.
May 2008—A judge in Niagara County sends Matt to state prison for 25 years to life after he is convicted of murdering Rickerson.
June 5, 2015—Matt and another convicted killer, David P. Sweat, are last seen in their cells during a 10:30 p.m. bed check at the Clinton State Correctional Facility in Dannemora.
June 6, 2015—Matt and Sweat are discovered to be missing during a 5:30 a.m. bed check. Crude dummies are found in their beds, and corrections officers find the men have escaped through a tunnel that took months to build. Hundreds of state troopers, police officers and federal agents begin searching for the two fugitives.
June 8, 2015—As investigators question prison employees, Joyce Mitchell, who had engaged in romantic relationships with Matt and Sweat while teaching them and other prisoners how to sew, is identified as a suspect. She is later charged criminally and imprisoned for helping the two men obtain tools they used to dig their tunnel.
June 26, 2015—After a huge statewide search during which hundreds of leads and false alarms were pursued, a federal agent shoots and kills Matt in Franklin County, about 40 miles from the prison. Police say Matt was killed after he refused orders to drop a gun he was carrying.
June 28, 2015—Sweat is shot, wounded and captured by State Police in Franklin County, a few miles from the Canada border.
June 6, 2016—A year after the breakout, the State Inspector General issues a report blaming “egregious and inexcusable” security lapses at the prison for the escapes.
The report notes that a dozen prison officials lost their jobs as a result of the incident. The report calls Matt and Sweat “particularly cunning and resourceful” inmates.
SOURCES: Buffalo News reports and state records