First graders attend a festive ceremony to mark the start of another school year in Slaviansk, September 1, 2014. September 1 marks the start of a new academic year for students in Ukraine. (Photo by Gleb Garanich/Reuters)

“The September 11 attacks (called September 11, September 11th or 9/11), were a series of four coordinated suicide attacks against targets in New York City and the Washington, D.C. area on September 11, 2001. On that morning, 19 terrorists from the Islamist militant group al-Qaeda hijacked four passenger jets. The hijackers intentionally crashed two planes into the Twin Towers of the World Trade Center in New York City; both towers collapsed within two hours. Hijackers crashed a third plane into the Pentagon in Arlington, Virginia. When passengers attempted to take control of the fourth plane, United Airlines Flight 93, it crashed into a field near Shanksville, Pennsylvania, preventing it from reaching its intended target in Washington, D.C. Nearly 3,000 died in the attacks”. – Wikipedia

Photo: A firefighter breaks down after the World Trade Center buildings collapsed September 11, 2001 after two hijacked airplanes slammed into the twin towers in a terrorist attack. (Photo by Mario Tama/Getty Images)

South Korean police officers show their martial arts' skills during the official launch ceremony of the 2012 Seoul Nuclear Security Summit on February 15, 2012 in Seoul, South Korea. The Korean National Police Agency launched a security squad, exclusively established for the successful hosting of the 2012 Seoul Nuclear Security Summit. The 2012 Seoul Nuclear Security Summit will be held in Seoul from March 26-27, 2012. (Photo by Chung Sung-Jun/Getty Images)

A guest proposes to his companion as they arrive for the screening of “Mektoub, My Love: Intermezzo” during the 72nd annual Cannes Film Festival, in Cannes, France, 23 May 2019. The movie is presented in the Official Competition of the festival which runs from 14 to 25 May. (Photo by Julien Warnand/EPA/EFE)

Caterine Ibarguen of Team Colombia competes in the Women's Triple Jump Qualification on day seven of the Tokyo 2020 Olympic Games at Olympic Stadium on July 30, 2021 in Tokyo, Japan. (Photo by Matthias Hangst/Getty Images)

Femen activists with their bare chests reading “Fascists out of ballot boxes” are held back by Catalan regional police forces Mossos d'Esquadra as they protest against far-right Vox party candidates in Barcelona during regional elections in Catalonia on February 14, 2021. Catalonia is voting in an election overshadowed by the pandemic which Madrid hopes will unseat the region's ruling separatists more than three years after a failed bid to break away from Spain. (Photo by Lluis Gene/AFP Photo/Profimedia)

A mother bear takes a dip in the water to cool off in the warm summer sun but refuses to leave her three youngsters behind – so they climb aboard her back. (Photo by Jon Langeland/Solent News & Photo Agency)