Swamp monkeys briefly escape enclosure at St. Louis Zoo

March 6 (UPI) -- Missouri's St. Louis Zoo said a pair of swamp monkeys briefly escaped from their enclosure before being captured in an area inaccessible to the public.

Zoo spokesman Billy Brennan said the habitat for the swamp monkeys, a species native to the swamp forests of Central Africa, was left unlocked during routine maintenance on the zoo's Primate House Saturday morning, allowing the two animals to escape.

The monkeys were located in a keeper hallway that is not accessible to the public, Brennan said. He said the primates were returned to their habitat.

The Primate House was temporarily closed to the public during the escape, Brennan said. He said zoo officials will review their safety and cleaning procedures.

The incident comes after an Andean black bear named Ben escaped from his enclosure twice within at single month at the Rivers Edge area of the zoo.