The massacre at the Tree of Life Synagogue in Pittsburgh, where 11 people were gunned down and six others were injured, is a tragic reminder of the world we live in today. Our deep condolences to all those affected.

The Tree of Life shooting is just the latest attack at a house of worship. In November 2017, 26 people were killed and 20 wounded at the First Baptist Church of Sutherland Springs, Texas. In August 2016, two people were killed at the Al-Fuqan Jame Masjid Mosque in New York City. In 2015, nine church members were shot to death at the Emanuel African Methodist Episcopal Church in South Carolina. In April 2015, three people died by gunfire at the Jewish Community Center of Greater Kansas City. There have been others.

A place of worship security guard can be a first line of defense, but other measures can be taken by the congregation. After the Sutherland Springs shooting, we offered suggestions on how to respond when faced with an active shooter. Sadly, we felt we needed run the list again.

Run. A person with a gun who is intent on shooting as many people as possible chooses victims that are easy targets. If you find yourself in an active shooter situation, keep your head down, try to conceal yourself and exit the area. A shooter will often come in through a main entrance. Look for other exit doors to escape. If you’re able to leave the shooting area, immediately alert others of the danger and call 911.

Hide. Sometimes, running to a storage room, empty classroom or bathroom is the only option. Once inside, lock and barricade the door, turn off the lights, silence your cell phone and move away from the door. Use anything you can to create another layer of protection around you—tables, chairs, shelving—anything that could stop or slow a bullet. Do your best to remain quiet.

Attack. If you are in an exposed area with nowhere to hide, attacking the shooter with improvised weapons is a last resort. Use anything to distract, confuse and disable the shooter.

Most active shooting incidents are over within minutes. When police arrive and it is safe, show your hands and follow instructions.