They thought he was a cute cat until his claws grew.

Staff at a German animal shelter got an unpleasant surprise when they discovered a seemingly abandoned kitten was actually an aggressive European wildcat.

A good Samaritan found the tiny creature on the road and after taking him home, she noticed he was feisty and refused to eat, so he brought her to the Tierheim Bergheim animal shelter. Dodo reported.

The sanctuary, located in Bergheim, about 40 kilometers from Cologne, immediately identified it as a European wildcat, about the size of a large domestic cat and a protected species endemic to the region.

Tierheim Bergheim posted a video of the cute animal suddenly hissing. Facebook pagewith a title explaining that it should be moved Retscheider Hofa wildlife station.

“The staff at the shelter immediately realized that this was no ordinary domestic kitten,” a spokesperson for the Retscheider Hof wildlife center said in a statement to the press.

“Certain characteristics and behaviors indicated that they were dealing with a wild cat. This prompted animal shelter staff to contact us immediately.”

The wildcat is currently at Retscheider Hof with another of its kind, and the pair will remain there until they are old enough to be released into the wild.

“We are currently working hard to provide both animals with the support and care they need,” the wildlife center spokesperson continued.

“We do our best to make their stay as comfortable as possible. Every progress they make is followed here with great excitement and hope.”