Residents recently returning to their area cleared by government troops react as they ride a tricycle a day after President Rodrigo Duterte declared the liberation of Marawi city in southern Philippines Wednesday, October 18, 2017. Sporadic explosions continue Wednesday as Philippine soldiers fought to gain control of the last pocket of Marawi controlled by Islamic militants. (Photo by Bullit Marquez/AP Photo)

In this 2017 photo provided by Simon Pierce, Jonathan Green checks on a fin-mounted satellite tag on a whale shark in the Galapagos Islands area of Ecuador. Despite typically being bigger than a double-decker bus, the elusive whale shark has only tiny, almost useless teeth. It's also one of the least understood animals in the ocean. (Photo by Simonjpierce.com via AP Photo)

A boy plays with pelicans in Yoff, commune of Dakar, Senegal March 14, 2018. (Photo by Zohra Bensemra/Reuters)

Russian cadets march during the annual cadet schools get-together in Moscow, Russia on March 30, 2018. (Photo by Mladen Antonov/AFP Photo)

A Buddhist nun walks along a path as a stupa is seen at a temple in Anuradhapura, Sri Lanka October 16, 2016. (Photo by Dinuka Liyanawatte/Reuters)

A truck driver cleans the mirror of his decorated truck in Charsadda outside Peshawar, Pakistan October 18, 2016. (Photo by Fayaz Aziz/Reuters)

Devotees whirl their head as a ritualistic performance during the annual Jhiri Fair at Kanachack village, outskirts of Jammu, India, Monday, November14, 2016. According to the villagers, the fair is held in memory of Baba Jitu, an honest farmer who killed himself since he was not prepared to submit to the unjust demands of a landlord who wanted him to part with his crop. (Photo by Channi Anand/AP Photo)

A woman walks past a caricature of Britain's Foreign Secretary Boris Johnson in east London, Britain November 18, 2016. (Photo by Andrew Winning/Reuters)