In this Wednesday, March 18, 2015 photo, limestone quarry workers walk through a cloud of dust spewed into the air by rotor blades of the stone-cutting machinery in the desert of Minya, southern Egypt. Around 45,000 people, including children, work in an estimated 1,500 quarries, digging out stones that later will be used in construction or powdered to be used by pharmaceutical and ceramic companies. (Photo by Mosa'ab Elshamy/AP Photo)

Serbian police officers of the Special Anti-Terrorist Unit pose for a picture in their base outside Belgrade October 8, 2014. When the killing of an unarmed black teenager by a white policeman in Ferguson, Missouri, in August sparked sometimes violent protests, the response of police in camouflage gear and armoured vehicles wielding stun grenades and assault rifles seemed more like a combat operation than a public order measure. Some U.S. police departments have recently acquired U.S. military-surplus hardware from wars abroad, but there are many law enforcers around the world whose rules of engagement also allow the use of lethal force with relatively few restrictions. But for every regulation that gives police wide scope to use firearms, there is another code that sharply limits their use. In Serbia, police may use measures ranging from batons to special vehicles, water cannon and tear gas on groups of people who have gathered illegally and are behaving in a way that is violent or could cause violence, but they may use firearms only when life is endangered. (Photo by Marko Djurica/Reuters)

Gloria Lincoln-Thompson carries her 9mm Smith & Wesson pistol in her waistband during a rally in support of the Michigan Open Carry gun law in Romulus, Michigan, in this April 27, 2014 file photo. (Photo by Rebecca Cook/Reuters)

The moon rises behind the skyline and financial district in Toronto, November 25, 2015. (Photo by Mark Blinch/Reuters)

Supporters of the United Democratic Party (UDP) opposition alliance presidential candidate, Adama Barrow attend a campaign rally in Buffer zone, Gambia November 29, 2016. (Photo by Thierry Gouegnon/Reuters)

October winner. “A burst of the aurora borealis over Kirkjufell, taken in September 2016. This shot has been a holy grail for me and was finally captured after many trips”. MICK RYAN, JUDGE: Iceland is a hotspot for aurora photography and this composition of the symmetric, free-standing Kirkjufell and the trident waterfall is much-sought after. If you can time your visit when the aurora “kp” index is high and know the settings for nighttime aurora images, you may end up with a beautiful photograph like this. (Photo by DВ/The Guardian)

In this Tuesday, December 20, 2016 photo, Mohammad Ramzan, right, reacts while talking to The Associated Press with his young bride Saima in Jampur, Pakistan. Saima was given as a bride to the older man by her father so he could marry the groom’s sister, a practice of exchanging girls that is entrenched in conservative regions of Pakistan. It even has its own name in Urdu: Watta Satta, “give and take”. A mix of interests – family obligations, desire for sons, a wish to hand off a girl to a husband – can lead to a young teen in an a marriage she never sought. (Photo by K.M. Chaudhry/AP Photo)

A jogger runs on the bank of Donaukanal channel in central Vienna, Austria, September 5, 2016. (Photo by Heinz-Peter Bader/Reuters)