**Watch is bedside interview in video player above**
The 32-year old gastroenterologist says he was consulting with other doctors and residents when Henry Bello burst into an office on the 16th floor and began firing. After playing dead and hiding in a bathroom, Dr. Hassan tried to go down the stairs to the emergency room. Instead he collapsed on the 12th floor due to blood loss. Colleagues picked him up and carried him directly into an operating room on the third floor. Dr. Hassan faces additional surgery and a long recovery, but is hopeful he will be able to resume practicing medicine.
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In all seven people were shot inside Bronx Lebanon Hospital.
The suspected gunman, Dr. Henry Bello used to work as a physician there, but was forced to resign two years ago.
Police said Bello fatally shot Dr. Tracy Tam. She had just started working at the hospital.
Update on injured victims: