The 24-year-old Bills safety had been showing signs of accelerated improvement in the days leading up to his release from Buffalo General Medical Center in New York, hospital officials had said.Hamlin initially was hospitalized in Cincinnati when his heart suddenly stopped after a tackle during a game against the host Cincinnati Bengals on January 2, but was transferred to the Buffalo facility Monday after doctors determined his critical condition had improved enough for the move.On Friday morning the breathing tube was removed, and Hamlin began walking with some help by that afternoon, his doctors said Monday.Swift response was key to saving HamlinWhen Hamlin collapsed seconds after an open-field tackle against a Bengals wide receiver, medical personnel rushed onto the field and administered CPR quickly – which helped save his life.Now, the Bills organization is encouraging people to learn the critical, life-saving skill of administering CPR."