THE head of an animal rescue centre in China says volunteers have rescued about 900 dogs that were being transported in a truck.

Chen Mingcai of the Chongqing Small Animal Protection Association said on Sunday that a citizen became suspicious of the truck and called police, who detained the truck driver on Friday night.

Chen says he was later contacted by someone who had seen a photo of the dogs left in the truck on the entrance of an expressway in southwestern Chongqing city.

By Saturday afternoon, Chen says volunteers from the animal center and other animal lovers who had seen postings about the dogs on social media had arrived at the truck wanting to help the canines.

Chen says many of the dogs looked like pet dogs.