Chinese authorities are using animals to test living conditions in Tianjin, where a giant chemical explosion last week killed 116 people.
Photographs show rabbits, pigeons and chickens in cages amid the devastation following the blast that has provoked fears of chemical contamination.
Local media reported the animals were still alive two hours after being placed at the site.
Authorities have said about 40 chemicals, including more than 100 tonnes of highly toxic sodium cyanide, were stored in the warehouse at the epicentre of the August 13 explosion.
In the week since, officials have tried to calm public fears of chemical dangers.
A 3.2km evacuation of the area surrounding the epicentre remains and locals remain reluctant to return home.
Tianjin deputy mayor Wang Hongjiang claimed 200 tonnes of sodium cyanide had been collected as the lengthy clean-up operation continued.
Contamination around the blast site was now under control and the density of air pollutants in the immediate area has reduced, he told Chinese news agency Xinhua.