Cho left the scene and returned to his room in Harper Hall, a dormitory west of West Ambler Johnston Hall. While police and emergency medical services units were responding to the shootings in the dorm next door, Cho changed out of his bloodstained clothes, logged on to his computer to delete his e-mails and his student university account, and then removed the hard drive. About an hour after the attack, Cho is believed to have been seen near the campus duck pond. Although authorities suspected Cho had thrown his hard drive and mobile phone into the water, a search by divers was unsuccessful.