A staff paints a model with camouflage colours to blend him in with the background for Chinese artist Liu Bolin's artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. In this artwork, Liu wants to express his concerns about China and its people, including air pollution problem, Liu told Reuters. (Photo by Kim Kyung-Hoon/Reuters)





Models pose before they are painted in camouflage colours to blend in with the background for Chinese artist Liu Bolin's artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. (Photo by Kim Kyung-Hoon/Reuters)





Models painted in camouflage colours to blend in with the background pose for Chinese artist Liu Bolin's artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. (Photo by Kim Kyung-Hoon/Reuters)





Models painted in camouflage colours to blend in with the background pose for Chinese artist Liu Bolin's artwork "“Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. (Photo by Kim Kyung-Hoon/Reuters)





Chinese artist Liu Bolin direct his models painted in camouflage colours to blend in with the background for his artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. (Photo by Kim Kyung-Hoon/Reuters)





Models painted in camouflage colours to blend in with the background pose for Chinese artist Liu Bolin's artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. (Photo by Kim Kyung-Hoon/Reuters)





A model painted in camouflage colours to blend in with the background waits to pose for Chinese artist Liu Bolin's artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. (Photo by Kim Kyung-Hoon/Reuters)





Models, painted in camouflage colours to blend in with the background, take a walk after practising for posing for Chinese artist Liu Bolin's artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. (Photo by Kim Kyung-Hoon/Reuters)





A models painted in camouflage colours to blend in with the background poses for Chinese artist Liu Bolin's artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. (Photo by Kim Kyung-Hoon/Reuters)





A staff paints a model with camouflage colours to blend her in with the background for Chinese artist Liu Bolin's artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. (Photo by Kim Kyung-Hoon/Reuters)





This combination picture shows models posing before (top) and after they are painted in camouflage colours to blend in with the background for Chinese artist Liu Bolin's artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. (Photo by Kim Kyung-Hoon/Reuters)





A model painted in camouflage colours to blend in with the background practises posing for Chinese artist Liu Bolin's artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. (Photo by Kim Kyung-Hoon/Reuters)





Models painted in camouflage colours to blend in with the background pose for Chinese artist Liu Bolin's artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. (Photo by Kim Kyung-Hoon/Reuters)