On Friday, October 9, 2009 at approximately 10:20am, while travelling on North Street (District A1-Downtown) a Boston Police Sergeant observed a large crowd gathered around a male lying on the ground. The Sergeant then observed a female conducting chest compressions on the unconscious adult male. The Sergeant rendered assistance and determined that the victim was not breathing and had no pulse. Retrieving his CPR face mask, the Sergeant began to conduct CPR. Another officer arrived on scene, relieved the female, and began chest compressions while the Sergeant performed rescue breathing. After about four cycles of CPR, the victim vomited into the CPR mask. The Sergeant then cleared the victim’s airway and the victim began breathing and his pulse was restored.