Joe Deedon, president of TAC ONE Consulting, demonstrates searching for a shooter in a middle school during an Active Shooter Response course offered by TAC ONE in Denver April 2, 2016. According to TAC ONE, the course, which is offered for the first time to concealed weapons permit carrying civilians, is designed at preparing people to effectively save lives prior to the arrival of law enforcement at an active shooter incident. (Photo by Rick Wilking/Reuters)

A passenger plane comes into land over a field containing horses at Heathrow Airport on August 11, 2014 in London, England. Heathrow is the busiest airport in the United Kingdom and the third busiest in the world. The airport's operator BAA wants to build a third runway to cope with increased demand. (Photo by Peter Macdiarmid/Getty Images)

A woman passes a mural in Manhattan on October 27, 2019 in New York City. (Photo by Johannes Eisele/AFP Photo)

A woman walks past a mural on a wall along a street in Singapore on February 17, 2021. (Photo by Roslan Rahman/AFP Photo)

A man poses for a photograph in front of a mural of Democrat US presidential nominee Hillary Clinton clad in a swimsuit bearing the colours of the US flag in West Footscray in Melbourne on July 30, 2016. An Australian mural of US presidential nominee Hillary Clinton in a revealing, stars and stripes swimsuit may be taken down, after it has reportedly been deemed offensive. (Photo by Paul Crock/AFP Photo)

In this September 16, 2017 photo, a music fan poses for the photo against an angel wings' mural at the Rock in Rio music festival in Rio de Janeiro, Brazil. (Photo by Leo Correa/AP Photo)

An artist (R) gives finishing touches to a New Year mural painted on his house in Chennai on December 29, 2022. (Photo by Arun Sankar/AFP Photo)

A mural is seen on a heavily damaged residential building in the frontline town of Avdiivka, Donetsk region on April 25, 2023, amid the Russian invasion of Ukraine. (Photo by Anatolii Stepanov/AFP Photo)