There’s a dark secret behind the viral video of playful, carefree Siberian tigers chasing down a flying drone in China.

The big cats are not only kept in horrible conditions — they’re bred to be slaughtered for their fur, meat and other body parts, shocking new reports revealed Friday.

The footage shows several tigers hunting down the drone, with one of them leaping up, knocking it to the snow-covered ground and then trying to eat it.

It was taken at the Harbin Siberian Tiger Park in northeast China, according to Vice’s Web site.

The 356-acre “park,’’ which has about 500 tigers, also produces an illegal brew called “tiger bone wine,” according to the report. The drink is actually made from the bones of tigers.

The animals at Harbin are kept in small, filthy cages, where they “roll around in their own excrement,’’ McClatchy newspapers reported in 2014. The report added that visitors can purchase live animals for the felines to hunt and eat.

The farm, which also has white tigers, lions and leopards, was described as “the largest natural park for wild Siberian tigers in the world” on Travel China Guide’s Web site.

Earlier this month, Harbin came under fire when pictures of its obese tigers raised concerns that the animals were actually sick, according to the South China Morning Post.

Obesity in tigers is a sign of illness.

The Washington Post quoted China Central Television, which released the video on Feb. 22, saying, “This drone chasing is becoming more popular among these well-nourished ­tigers in the habitat.’’

About 200 tiger farms — where as many as 65,000 tigers live in captivity — still exist in China.