A man presents a self-made robot that local media reported is able to carry a person, in Heihe, Heilongjiang province, China, April 5, 2017. (Photo by Reuters/China Daily)

Russian servicewomen march during the Victory Day Parade in Red Square in Moscow, Russia, June 24, 2020. The military parade, marking the 75th anniversary of the victory over Nazi Germany in World War Two, was scheduled for May 9 but postponed due to the outbreak of the coronavirus disease (COVID-19). (Photo by Sergey Pyatakov/Host Photo Agency/AFP Photo)

A Ukrainian serviceman wearing a new year's hat waves at his comrades while standing beside his tank near Debaltseve, eastern Ukraine, February 8, 2015. (Photo by Gleb Garanich/Reuters)

A pro-Russian rebel shows his t-shirt depicting Russian President Vladimir Putin at a checkpoint in the village of Chornukhyne near the town of Debaltseve, north-east from Donetsk, March 12, 2015. (Photo by Marko Djurica/Reuters)

The feet of a Filipino penitent is nailed to a wooden cross during Good Friday rituals on April 3, 2015 at Cutud, Pampanga province, northern Philippines. Several Filipino devotees had themselves nailed to crosses Friday to remember Jesus Christ's suffering and death, an annual rite frowned upon by church leaders in this predominantly Roman Catholic country. (Photo by Aaron Favila/AP Photo)

A resident jumps as he watches strong waves crash into shore as an effect of Typhoon Hagupit in Legazpi, Albay province, eastern Philippines on Sunday, December 7, 2014. Typhoon Hagupit knocked out power in entire coastal provinces, mowed down trees and sent more than 650,000 people into shelters before it weakened Sunday, sparing the central Philippines a repetition of unprecedented devastation by last year's storm. (Photo by Aaron Favila/AP Photo)

A woman poses for a photograph in front of a 3D painting at HK 3D Museum in Hong Kong June 26, 2014. (Photo by Tyrone Siu/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)