A Ukrainian serviceman fires a 2S7 Pion self-propelled gun during military exercises near the village of Divychky in Kiev region, Ukraine, October 21, 2016. (Photo by Valentyn Ogirenko/Reuters)

Members of the Indonesian Presidential Security Forces (Paspampres) show their skills during the simulation of a terrorist attack in Jakarta, Indonesia, 29 December 2016. According to reports in local media the Indonesian security forces have already arrested 21 terrorists suspects and fatally shot five of them, who were allegedly planning attacks in the Indonesian capital during the Christmas and New Year's Eve celebrations this year. The presentation was shown on the occasion of a visit by Indonesian President Joko Widodo and a delegation to the Paspampres headquarters in Jakarta. (Photo by Bagus Indahono/EPA)

Firefighters watch as an air tanker drops retardant while battling the Ferguson fire in the Stanislaus National Forest, near Yosemite National Park, California on July 21, 2018. A fire that claimed the life of one firefighter and injured two others near California's Yosemite national park has almost doubled in size in three days, authorities said Friday. (Photo by Noah Berger/AFP Photo)

A woman takes a selfie in front of a Lunar New Year display featuring sheep at a shopping mall in Hong Kong, February 13, 2015. (Photo by Bobby Yip/Reuters)

Passengers embrace each other at the entrance to Istanbul's Ataturk airport, early Wednesday, June 29, 2016 following their evacuation after a blast. Suspected Islamic State group extremists have hit the international terminal of Istanbul's Ataturk airport, killing dozens of people and wounding many others, Turkish officials said Tuesday. (Photo by Emrah Gurel/AP Photo)

Indian folk dancers display ornaments during a break while participating in the first night of Navratri in Gandhinagar, some 30 km from Ahmedabad, on October 13, 2015. Navratri festivities, or Dance Festival of Nine Nights, takes place between October 13-21. (Photo by Sam Panthaky/AFP Photo)

A doll, placed by stranded Iranian migrant protesters, hangs from barbed wire in front of Madedonian police at the Greek-Macedonian border near to the Greek village of Idomeni November 29, 2015. The protesters were demonstrating against what they say is the closure of the border for Iranian migrants. According to the demonstrators, the hanging toys and dolls represent the outcome of being unable to return, if they are sent back to Iran. (Photo by Yannis Behrakis/Reuters)

Participants of an unauthorized opposition rally gather in Tverskaya street in central Moscow on June 12, 2017. Authorities detained Russian opposition politician Alexei Navalny and hundreds of his supporters on Monday, as they mounted demonstrations across the nation against government corruption. Over 200 were detained in Moscow and Saint Petersburg an hour into the protest, according to an NGO that tracks arrests, with Navalny himself picked up by police in his building as he was headed to the event. (Photo by Vasily Maximov/AFP Photo)