A bunker at aformer Swiss artillery fortress called Heldsberg stands near the town of St. Margareten, Switzerland March 22, 2015. Heldsberg fortress, located on the Swiss-Austrian border near the River Rhine and Lake Constance was built from 1938 to 1940 and remained in military use until 1992. Since 1993 it is open to the public as Fortress Museum Heldsberg. (Photo by Arnd Wiegmann/Reuters)

An employee walks near a rotary dredge which works on the coal face of the Borodinsky opencast colliery, near the Siberian town of Borodino, east of Krasnoyarsk, December 9, 2014. The Borodinsky colliery, 9 km (5.6 miles) long and more than 100 meters (328 feet) deep, annually produces more than 20 million tons of coal and is considered to be the biggest opencast coal mine in Russia, according to official representatives. (Photo by Ilya Naymushin/Reuters)

A policeman stands near a burning vehicle during clashes between supporters of former prime minister Imran Khan and riot police near Khan's house to prevent officers from arresting him, in Lahore on early March 15, 2023. Pakistan police appeared on March 15 to have given up an attempt to arrest former prime minister Imran Khan, ending a siege of his residence after violent clashes with hundreds of his supporters. (Photo by Arif Ali/AFP Photo)

Three Japanese tourists had to abandon plans to drive to Stradbroke Island off the Queensland coast when their hire car became bogged in mangrove mud, on March 15, 2012 near Stradbroke Island, Australia. (Photo by Chris McCormack/Fairfax Media).

A girl laughs while unloading her boat of produce at a market in Ganvie on January 6, 2012 in Cotonou, Benin. Often called the Venice of Africa, Ganvie is a stilted fishing village on Lake Nokoue, near Cotonou in Benin, the largest such village in Africa, and home to approximately 20,000 residents. (Photo by Dan Kitwood/Getty Images)

An Israeli missile is launched from the Iron Dome missile system in response to a rocket launch from the nearby Palestinian Gaza Strip, on March 12, 2012 near Ashdod, Israel. (Photo by Uriel Sinai/Getty Images)

A meteorite burns up in the atmosphere as seen in this photo taken near of Salgotarjan, 109 kms northeast of Budapest, Hungary, late 21 April 2015. The Moon and Venus can be seen on the left. (Photo by Peter Komka/EPA)

Birds made of recycled tires are displayed in a shop located on the Panamerican highway near Catarina town, May 7, 2015. Salazar recycles used tyres to make bird figurines and sofas to sell in his shop located on the Panamerican highway. (Photo by Oswaldo Rivas/Reuters)