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Terrorism and mass attacks

Terrorism and mass attacks

The FBI categorizes terrorism as either domestic or international.

Domestic terrorism:  Violent, criminal acts committed by individuals and/or groups to further ideological goals stemming from domestic influences, such as those of a political, religious, social, racial, or environmental nature. 

International terrorism: Violent, criminal acts committed by individuals and/or groups who are inspired by, or associated with, designated foreign terrorist organizations or nations (state-sponsored). 

The U.S. Secret Service defines mass attacks as incidents in which three or more people, not including the attacker(s), were harmed.  The Department of Homeland Security (DHS) categorizes by the weapon used, including firearms, vehicles, bombs, knives, fires, drones, or other weapons.

While the threat of terrorism and mass attacks is real, there are a number of things you can do to prepare for, protect yourself from, and help others after these types of incidents.


If you see something suspicious or that doesn't seem quite right, say something by calling 9-1-1 to report it. By being alert and reporting suspicious activity to your local law enforcement, you can protect your family, neighbors, and community.

• What is suspicious activity? Any observed behavior that could indicate terrorism or terrorism-related crime.  More information here.

See Something, Say Something emphasizes behavior, not appearance, in identifying suspicious activity.  Learn to recognize the signs of terrorism-related suspicious activity.

• For more information, visit the See Something, Say Something campaign website: If You See Something, Say Something® | Homeland Security (


•Be aware of your surroundings and any possible dangers

•Practice “See Something, Say Something”

•Have an exit plan

•Make a Plan, Build a Kit, Help Each Other – Make it Through

•Learn lifesaving skills, including how to Stop the Bleed


• Run away from the attack, if you can do so safely; call 9-1-1

• If you cannot run away, find a place to hide and take cover; call 9-1-1

• Stay and fight, only as a last resort

Run, Hide, Fight

ReadyHouston produced a video with a realistic enactment of an active shooter event. This video may be disturbing. Viewer discretion is advised.

Be Safe After

• Help the wounded, once safe to do so

• Cooperate with law enforcement

Other tips and tricks to help you prepare

• Listen to your NOAA Weather Radio or local media for current information.

• Take precautions when traveling.  Be aware of conspicuous or unusual behavior.  Do not accept packages from strangers.  Do not leave your luggage unattended.

• Know the emergency evacuation procedures that are in place for the business or building.  Know where fire exits are located and be able to find them in the dark.  Learn where fire extinguishers are located and how to use them.  Know where disaster supplies are located.

• Work with building management to ensure the following items are located on each floor of the building: portable battery-operated radio and extra batteries, flashlights and extra batteries, first aid kit and manual, hard hats, dust masks, and fluorescent glow-in-the-dark tape to rope off dangerous areas.

For more information and details on what you can do:
• DHS: Attacks in Crowded and Public Spaces |
• FBI: Active Shooter Resources — FBI

Stop the Bleed is a national awareness campaign and call-to-action. Stop the Bleed is intended to cultivate grassroots efforts that encourage bystanders to become trained, equipped, and empowered to help in a bleeding emergency before professional help arrives.

To learn more or get involved, visit:
• DHS: Stop the Bleed | Homeland Security (
• Stop the Bleed: Home | Stop The Bleed

You can also contact us to see if a Stop the Bleed training course is being offered locally, and to learn more about Stop the Bleed mass care kits around the region.
Sophia Lopez, EM Program Manager, 206-205-6545

Terrorist targets tend to be located in urban areas with venues such as seats of government, stadiums, and public meeting places. Terrorists target these areas to incite fear and produce substantial news coverage. Terrorist attacks come in many forms and may involve bombings, hijackings, assassinations, kidnappings, cyber attacks (computer-based), and the use of explosives, chemicals, biological agents, and nuclear or radiological weapons.

Terrorism breeds fear, frightens our families, and creates instability in our community. Many Americans don't understand vague directives from officials advising us to be "more vigilant" in our awareness of suspicious activity, and wonder what they can do to help themselves and their community. This is especially difficult when acts of terrorism foster a feeling of insecurity, helplessness, and most importantly, a feeling that you can't prepare for the possibility of a terrorist act.

• Try to remain calm and be patient.
• Do not call 9-1-1 unless you have a life-threatening emergency.
• Follow the advice of local emergency officials. If advised to evacuate or shelter-in-place, do so immediately.
• If the disaster occurs near your home while you are there, check for damage using a flashlight. Do not light matches or candles or turn on electrical switches. Check for fires, fire hazards, and other household hazards. Sniff for gas leaks, starting at the water heater. If you smell gas or suspect a leak, turn off the main gas valve, open windows, and get everyone outside quickly.
• Confine or secure your pets.

If you receive a bomb threat:
• Get as much information from the caller as possible.
• Keep the caller on the line and record everything being said.
• Notify the police and the building management.

If an explosion occurs:
• Immediately get under a sturdy table or desk if things are falling around you. When they stop falling, leave quickly, watching for obviously weakened floors and stairways. As you exit the building, watch for falling debris.
• Heavy smoke and poisonous gases collect first along the ceiling. Stay below the smoke at all times.
• Leave the building as quickly as possible. Do not stop to retrieve personal possessions or make phone calls.
• Once you are out, stand away from windows, glass doors and other potentially hazardous areas. Move away from sidewalks or streets that are to be used by emergency workers and others still exiting the building.

If you're trapped in debris:
• If you have a flashlight, use it to signal rescuers.
• Avoid unnecessary movement and stay in your area so you don't kick up dust.
• Cover your mouth with a handkerchief or clothing.
• Tap on a pipe or wall so rescuers can locate you. If possible, use a whistle. Shout as a last resort - shouting can cause a person to inhale dangerous amounts of dust.

If there's a fire:
• Stay low to the floor and exit the building as quickly as possible.
• Test closed doors for heat with your hand before opening. If the door is not hot, brace your body against the door and open slightly to check for fire or smoke. If the door is hot, seek an alternate escape route.
• If you cannot escape, put as many barriers and space between you and the fire as possible.
• If you have access to a phone, call 9-1-1 and report your location.

If biological agents are involved:
If you become aware of an unusual or suspicious substance nearby:
o Move away quickly.
o Wash with soap and water.
o Contact authorities.
o Listen to your NOAA Weather Radio or monitor local media for official instructions.
o Seek medical attention if you become sick.

If you are exposed to a biological agent:
o Remove and bag your clothes and personal items. Follow official instructions for disposal.
o Wash yourself with soap and water and put on clean clothes.
o Seek medical assistance. You may be advised to stay away from others or be quarantined.

Other types of events:
• If chemicals are involved, see the hazardous materials section.
• If the attack involves a nuclear blast or a radiological dispersion device (RDD) or dirty bomb, see the radiation hazards section.


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