Active Shooter

Active Shooter

What is an Active Shooter?
An active shooter is a person or persons who appear to be actively engaged in killing or attempting to kill people in populated areas on campus. In most cases active shooters use a firearm(s) and display no pattern or method for selection of their victims. In some cases active shooters use other weapons and/or improvised explosive devices to cause additional victimization and act as an impediment to law enforcement and emergency services responders. These improvised explosive devices may detonate immediately, have delayed detonation fuses, or detonate on contact.

What makes an Active Shooter situation different from a hostage or barricaded subject situation?
Active shooter situations are dynamic and evolve rapidly, demanding immediate response by the community and immediate deployment of law enforcement resources to stop the shooting and prevent further harm to the community.

Hostage or barricaded subject situations often take place over a longer period of time and usually there is no ongoing injury or loss of life. These situations are often managed through the deployment of specialized units, as time allows. Both hostage and barricaded subject situations can rapidly shift to Active Shooter situations and vice versa.

What should I do if I find myself involved in an Active Shooter situation?

If you find yourself involved in an active shooter situation, or a situation that has the potential for extreme violence, try to remain calm and follow these procedures:

1. Report

Call 911 and state “I’m calling from Weill Cornell Medicine. We have an active shooter on campus, gunshots fired.”

When safe to do so, also call Security at 212-746-0911 (on campus) or the Building Front Desk (off campus).


  • Your exact location
  • Description of the offender(s) (Details including sex, race, clothing, type of weapon(s), location last seen, direction
  • of travel and identify if known)
  • Description and location of any victims
  • Details of the situation (If you observed any suspicious devices <improvised explosive devices> or heard explosions, provide the location seen and a description

NOTE: If you have a panic button, use it

2. Alert

  • Warn other students, faculty, staff, patients and visitors to take immediate shelter (or action)
  • If responsible for patients, do not leave your patients

3. Evacuate or Shelter

  • If there is an escape path, attempt to evacuate but do not leave patients unable to escape
  • Move to an area where the active shooter cannot see you
  • Move away from the sound of gunshot(s) and/or explosion(s)

✓ Go to a room that can be locked or barricaded
✓ Lock and barricade doors and windows
✓ Take adequate cover/protection (i.e., concrete walls, thick desks, filing cabinets)
✓ If outdoors, take appropriate cover/protection (i.e., brick walls, parked vehicles)

✓ Turn off lights, close window blinds, and block windows

✓ Turn off any devices that emit sound (i.e., cell phones, radios)

4. Listen

  • Listen for updated announcements and law enforcement arrival
  • Do not respond to voice commands until you can verify with certainty that they are being issued by a law enforcement officer or university official; unfamiliar voices may be an active shooter trying to lure you from safety

5. When Law Enforcement Arrives:

  • Do exactly as the team of officers instructs
  • Do not approach the officers
  • Keep your hands visible, fingers spread and empty

See also: PDF icon Active Shooter Bulletin

Contact Information

Environmental Health and Safety 402 E. 67th Street,
Room LA-0020
New York, NY 10065 Phone: (646) 962-7233 Fax: (646) 962-0288