A US Marine leads two Viet Cong suspects in restraints during the Tet Offensive on February 20, 1967. (Photo by Bettmann Archive/Getty Images)

A portrait of French WWI soldier Edouard Marius Ivaldi is displayed on a tablet, in this illustration picture, alongside his battlefield grave memorial, a wooden cross with a battlefield helmet in Champagne, eastern France, November 3, 2015. (Photo by Charles Platiau/Reuters)

Cosplayers dressed as characters from the Star Wars movie series visit patients during a charity event organised by non-profit group 501st Legion, at East Avenue Medical Center in Quezon city, metro Manila December 6, 2015. (Photo by Romeo Ranoco/Reuters)

Medic James E. Callahan of Pittsfield, Mass., gives mouth-to-mouth resuscitation to a dying soldier in war zone D, about 50 miles northeast of Saigon, June 17, 1967. Thirty-one men of the 1st Infantry Division were reported killed in the guerrilla ambush, with more than 100 wounded. (Photo by Henri Huet/AP Photo)

On the streets of Kunming, Yunnan Province, you can find odd couple – a dog and a cat who sits on his four-legged companion. They are Vantsay and Mimi. The owner of animals, a 42-year-old retired policeman Xu Jin is surprised with so strong friendship. “When I got the dog, and I began to take her for a walk, the cat became plaintive, – says the man. – So I bought a leash and began to take her too. Soon, however, the cat began to tire and quickly realized that it is much easier to ride on the back of a dog. ”

Period-costumed actors participate in the 150th anniversary re-enactment of the surrender of General Robert E. Lee to General Ulysses S. Grant at the Museum of Confederacy in Appomattox, Virginia, April 9, 2015. (Photo by Jay Paul/Reuters)

A photographer has captured the bizarre beauty of sphynx cats in a series of intriguing portraits. Creative Alicia Rius snapped them from different angles showing off their unusual flesh, colourings and bones. In the images the cats can be seen curiously playing, observing their surroundings and even grooming themselves. (Photo by Alicia Rius/Caters News)

National Geographic photographer Steve Winter has spent most of his adult life shooting wild cats. Photo: A 14-month-old cub, cooling off in a pond, is riveted by a deer that appeared near the shore. Tigers are powerful swimmers; they can easily cross rivers four to five miles wide and have been known to swim distances of up to 18 miles. (Photo by Steve Winter/National Geographic)