Hibernating crocodiles were stoned by visitors at a zoo in Shenzhen, Guangdong province, because the sightseers wanted to check they were alive.

Visitors hurled bottles, rubbish and even stones at the sleeping reptiles, turning a blind eye to signs erected around the crocodile pool urging people not to disturb the animals, an official from the zoo said.

Zookeepers urged visitors to behave themselves.

"It is hard to keep an eye on every visitor all the time," the official said.

According to the official, the zoo used to have five to six crocodiles, but now they only have two.

He warned visitors that teasing crocodiles can be dangerous because if the reptiles are provoked, they will attack people.

Contact the writer at yangyao@chinadaily.com.cn