A police officer has come under criticism after shooting dead a bear that had escaped from a circus.

Two brown bears, named Nena and Katja, managed to get out of their enclosure on Sunday morning as the circus prepared for a performance to an audience of hundreds of children in the western German city of Kassel.

A motorist on a nearby highway saw Nena and informed the police. A patrol car discovered the bears next to the four-lane road. One officer stopped traffic while the second policeman attempted to shoo the bear away from the road and back toward the circus.

However, Nena attacked the cop and bit him twice on the left calf. The injured policeman shot the 180-kilogram (397-pound) bear five or six times with his service pistol. At least one bullet hit the bear in the shoulder while another hit her in the head. Police were able to stop the other bear, Katja, who was caught by circus employees and led back to her enclosure.

The circus director was sharply critical of the police action, which he described as "out of proportion." Nena was "like a member of the family," Daniel Renz, who is the eighth generation of his family to run the Universal Renz circus, told the news agency DPA. "At the age of 25, she hardly has any teeth any more. I could have led her by the ear back to the cage again and the whole thing would have been over in five minutes."

"They gave us no chance to catch the animals," Renz said. "They just fired away like macho men."

However the police defended their actions. "One of the animals bit the officer in the leg," a senior officer told DPA. "If that's not danger in progress, then I don't know what is."

"On one side of the bear were 800 people, most of them children. On the other side were two busy main roads. If the officer hadn't done something, he would have been reprimanded," commented another policeman.

It is still unclear how the bears managed to escape from the circus enclosure. "Well, it's possible that the door wasn't properly secured," Renz admitted.