U.S. singer Katy Perry slips on the icing of a giant cake that she had jumped onto as part of her performance at the MTV Latin America Awards in Guadalajara, in this October 16, 2008 file photo. (Photo by Daniel Aguilar/Reuters)

Xie Guobiao (C), 11, tied to a pillar with a rope, cries as his grandmother (L) and younger sister look on at his home in Daohui village of Lishui, Zhejiang province May 7, 2014. Xie was diagnosed as mentally handicapped when he was young, but the family was not able to provide him with sufficient medical treatment because of poverty. At the age of six, Xie started to sneak out of his home when others were not looking, climbing on top of houses and smashing windows. Xie's family had to pay over 10,000 yuan ($1,606) in compensation to others for the damage he caused. Since then, the family has had to tie Xie up with a rope both at home and in public, they said. (Photo by William Hong/Reuters)

A polar bear plays with a pylon during celebrations marking its first birthday in an enclosure at Tierpark Hellabrunn zoo in Munich December 9, 2014. (Photo by Michaela Rehle/Reuters)

The provincial highest chimney collapses as it is demolished by explosives in Shenyang, Liaoning province, April 28, 2014. The 150-metre-high chimney used to be part of a local heating factory, according to local media. (Photo by Sheng Li/Reuters)

American model Isabella Khair Hadid is seen on March 13, 2018 in Los Angeles, California. (Photo by The Mega Agency)

Personal trainer, Denise Austin, and Katie Austin arrive at the ESPY Awards at the Microsoft Theater on Wednesday, July 13, 2016, in Los Angeles. (Photo by Jordan Strauss/Invision/AP Photo)

Kevin Kvasnicka (L) and Jesse Gonzales openly carry firearms as they watch U.S. Republican presidential nominee Donald Trump speak on a big screen television along East 4th street during the Republican National Convention in Cleveland, Ohio, U.S., July 21, 2016. (Photo by Adrees Latif/Reuters)

A man takes a picture of models as they pose next to Cosmis Racing Wheels products during the 2016 Moscow International Auto Salon in Moscow, Russia, August 26, 2016. (Photo by Sergei Karpukhin/Reuters)