The photo shows a scrawny tiger at Tianjin Zoo. [Photo provided by netizen]

Photos of a scrawny tiger at a Tianjin zoo have aroused a flood of criticism online against the zoo, following suspicions that the animal was mistreated.

A netizen on Friday posted photos of the tiger that he shot at the Tianjin Zoo. On the photos, the tiger appears to have no external suggestion of fat, and is reduced to little more than skin and bone.

The netizen said he nearly cried when he saw the tiger and wondered how he could help it.

The head of the zoo, who denied the accusation of mistreatment, told CCTV that the tiger was diagnosed with a disorder of the digestive system after it was born in 2001. It had recovered a lot from the illness, but the disease worsened with age, he said.

A local veterinary hospital also showed a statement of diagnosis.

There are seven tigers at the zoo, and other six are all in good condition.

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