Gunfire was brought to the steps of President Truman's Washington home, Blair House, as two assassins tried to kill the chief executive, November 1, 1950. One of the gunmen, Oscar Collazzo of New York, lay wounded at the bottom of Blair House's front steps after the president's police guard had finished their work, at the cost of one guards' life, Dec. 9, 1950. The second gunman was killed. (Photo by Harvey Georges/AP Photo)

In this photograph taken on June 11, 2018, Chinese artists performs during a Indo-China cultural exchange program in Kolkata, West Bengal, India. (Photo by Dibyangshu Sarkar/AFP Photo)

Some people prepare to catch offerings thrown by Tengger tribe people into the crater of Bromo volcano to in Probolinggo, East Java province, on June 30, 2018, as part of Yadnya Kasada festival which falls on the 14th day of the Kasada month based on the traditional Hindu lunar calendar. (Photo by Juni Kriswanto/AFP Photo)

A commercial airline landing at the Princess Juliana International Airport in St Maarten on July 9, 2018. Ukrainians Oleg Kolisnichenko, 36, and Yulia Nos, 25, have been blasted for the “stupid stunt” on Maho Beach, which lies next to the main airport on the Caribbean island of Saint Martin. The stunt was met with criticism rather than praise from social media users. (Photo by SWNS: South West News Service)

Firefighters use a rope to rescue a group of people stranded in a flooded street on July 12, 2018 in Chengdu, Sichuan Province of China. A strong storm has hit many parts of southwest China's Sichuan Province since Monday, causing landslides and floods in the region. (Photo by Wang Hongqiang/Chengdu Economic Daily/VCG)

A unidentified woman protests at Broad Street for the pending arrival of Vice President Mike Pence at the Union League, in Philadelphia, Monday, July 23, 2018. Dozens of demonstrators dressed as characters from the novel-turned-TV series “The Handmaid's Tale” descended on downtown Philadelphia to protest Pence’s visit. (Photo by Jose F. Moreno/The Philadelphia Inquirer via AP Photo)

A Russian police officer detains a teenager during rally protesting retirement age hikes in St. Petersburg, Russia, Sunday, September 9, 2018. A government plan to increase the age for collecting state pensions brought protests across Russia's 11 time zones on Sunday even though the opposition leader who called them was in jail. Nearly 300 people were reported arrested. (Photo by Roman Pimenov/Interpress photo via AP Photo)

Six new Canadians take their oath of citizenship while harnessed on the CN Tower's “Edgewalk” 356 metres (1,168 feet) above Toronto, Ontario, Canada in a still image from video October 9, 2018. (Photo by CN Tower/Handout via Reuters)