File photo of Macaque monkeys (otherwise known as snow monkeys).

PORTLAND, Ore. (AP) - Employees from the Oregon National Primate Research Center were attempting to capture four monkeys that escaped after their cage was cleaned Friday afternoon.

The monkeys (which are Macaques, or snow monkeys) were last seen along the south edge of the university's west campus in Beaverton - an area near a light-rail line, said Jim Newman, an Oregon Health & Science University spokesman. The monkeys are too fast to catch, so caretakers were trying to lure them into cages baited with apples.

Newman said the monkeys pose little danger because they retreat from humans. Threatened monkeys, however, will bite and their saliva could contain a virus that harms people.

The escape occurred when a caretaker cleaned an outdoor cage that housed nine monkeys. The worker forgot to put the lock back on, and the monkeys figured out how to slide the door open, Newman said. Four monkeys were quickly captured, one was caught in the evening and four remain on the loose.

OHSU did not alert the public until the monkeys ventured near the rail line. A 10-foot chain-link fence, topped with barbed wire, serves as a barrier between the campus and the train.

The primate center affiliated with OHSU has long been criticized by animal-rights groups, who say the research monkeys are mistreated. Newman said OHSU does not believe the employee who forgot to lock the cage is an activist who got a job at the primate center.

Newman said the escapees are breeding monkeys and no tests were being conducted on them.
      
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