By Brian Burnes, The Kansas City Star

KANSAS CITY, MO — It wasn’t careless zookeepers that were responsible for the escape of seven chimpanzees from their Kansas City Zoo enclosure on Thursday afternoon.

It was clever chimpanzees.

That was zoo director Randy Wisthoff’s explanation for the unauthorized excursion that prompted a “Code Red” response among zoo employees, an hourlong lockdown of zoo visitors and finally a careful roundup.

“Chimps are so smart,” Wisthoff said.

One of them, he said, either found or broke off a 5- or 6-foot log or branch, leaned it against a wall and clambered to the top. Then that chimpanzee — the “ringleader,” Wisthoff called him — persuaded six friends to join him.

At one point, three of the seven chimps went over the wall into an area accessible only to zoo employees. Well before then, however, the zoo had activated its emergency protocols, which included gathering visitors into locked and secure areas.

At no time was the public in danger, Wisthoff said.

The breakout happened about 3:30 p.m., and it took about an hour for zookeepers to herd the animals, in groups of two or three, back into their enclosure.

The chimps were lured with fruit and greens such as carrots, celery and lettuce, their usual feed.

“It was almost their dinnertime already,” Wisthoff said.

But for the last reluctant animal, zookeepers brought out a bag of malted milk balls.

“That was the clincher,” Wisthoff said.

All employees were aware of the dangers the chimpanzees could have posed, Wisthoff said. Of the seven, the largest weighed about 150 pounds.

“They are tremendously strong,” he said.

Photo: Nigel Woollard via Flickr