School teachers and staff members take part during an active shooter training at James I. O'Neill High School in Highland Falls, New York, U.S., December 12, 2017. (Photo by Eduardo Munoz/Reuters)

An Army Sikorsky R-5 helicopter, undergoing record trials, demonstrates its lifting power by carrying 17 persons and pilot aloft as female onlookers wave in Bridgeport, Conn., January 10, 1946. During the tests records were claimed for altitude speed and both altitude and speed with payload. (Photo by Anthony Camerano/AP Photo)

A Palestinian woman reacts after inhaling tear gas fired by Israeli forces during a protest marking Land Day and the first anniversary of a surge of border protests, at the Israel-Gaza border fence, in the southern Gaza Strip on March 30, 2019. (Photo by Ashraf Abu Amrah/Reuters)

Fans and community members gather around a LAPD car along the procession route for Nipsey Hussle after his memorial at the Staples Center in Los Angeles, California, April 11, 2019. 4 people shot and 1 dead during the procession LAPD reported on late April 11, 2019 The Grammy-nominated artist was killed in front of The Marathon Clothing store he founded in 2017. (Photo by Kyle Grillot/AFP Photo)

A cosplayer poses during Day 2 of London MCM Comic Con 2019 at ExCel on May 25, 2019 in London, England. (Photo by Jack Dredd/Rex Features/Shutterstock)

One of a members of the Franciscan Action Network and immigration rights activists is arrested during a demonstration calling for the end of immigrant detention on Capitol Hill in Washington, U.S., July 18, 2019. (Photo by Joshua Roberts/Reuters)

Riot police help an injured anti-government protester after scuffles broke out with women police officers on a road leading to the parliament building, during a protest in Beirut on November 19, 2019. Thousands of protesters rallying against the Lebanese political elite blocked roads in central Beirut on Tuesday, preventing lawmakers from reaching the parliament and forcing the postponement of a legislative session. (Photo by Bilal Hussein/AP Photo)

A Kenya Wildlife Services (KWS) veterinarian and security personnel back away from a tranquilised black-Rhino calf August 30, 2017 after she appeared to prematurely overcome the sedative at the Nairobi National Park, during an identification-tagging excercise to ease quick identification of resident rhino during anti-poaching patrols. (Photo by Tony Karumba/AFP Photo)