An aerial view shows a sinkhole 3.5 km (2 miles) to the east of Solikamsk-2 mine in Perm region, November 20, 2014. Shares in Russia's Uralkali, the world's top potash producer, fell sharply for a second day on Wednesday after a mine accident that could reduce global supplies and push up prices of the crop nutrient worldwide. Uralkali shares have fallen 28 percent since Tuesday when it suspended work at its Solikamsk-2 mine, which accounts for a fifth of the company's output and 3.5 percent of global capacity, following an inflow of water. A sinkhole, stretching 30 by 40 metres (yards), found at an abandoned mine 3.5 km (2 miles) to the east, increased concern about the future of the mine because an inflow of water and the resulting sinkhole in 2006 forced another Uralkali operation to shut permanently. (Photo by Reuters/Press service of Uralkali company)

Edibles are displayed at Shango Cannabis shop on first day of legal recreational marijuana sales beginning at midnight in Portland, Oregon October 1, 2015. The sale of marijuana for recreational use began in Oregon on October 1, 2015 as it joined Washington state and Colorado in allowing the sale of a drug that remains illegal under U.S. federal law. (Photo by Steve Dipaola/Reuters)

Deers walk past Indonesia's honour guard as they wait for the arrival of Saudi Arabia's King Salman bin Abdul Aziz at the presidential palace in Bogor on March 1, 2017. Cheering crowds welcomed King Salman on March 1 as he began the first visit by a Saudi monarch to Indonesia for almost 50 years, seeking stronger economic ties with the world's most populous Muslim-majority country. (Photo by Adek Berry/AFP Photo)

A woman reacts after she was hit with pepper spray deployed by police as they cleared a street with protesters rallying against a new national security law in Hong Kong on July 1, 2020, on the 23rd anniversary of the city's handover from Britain to China. A man found in possession of a Hong Kong independence flag became the first person to be arrested under Beijing's new national security law for the city, police said on July 1. (Photo by Dale De La Rey/AFP Photo)

This undated handout photograph released by Stony Brook University/ Louisiana State University on March 2, 2018, shows an Adélie penguin looking at a drone at breeding colony on Heroina Island, Danger Islands, Antarctica. A thriving “hotspot” of some 1.5 million Adelie penguins has been discovered on the remote Danger Islands in the east Antarctic, surprised scientists announced on March 2, 2018. (Photo by Rachael Herman/AFP Photo/Louisiana State University AND Stony Brook University)

A Swiss police officer accompanies a migrant from Syria carrying her baby, upon her arrival at the railway station in the north-eastern Swiss town of Buchs September 1, 2015. (Photo by Arnd Wiegmann/Reuters)