Editor's note: The two missing monkeys in this story were found safe Tuesday. Click here for the full story.
The Dallas Zoo says two emperor tamarin monkeys are missing and that there's clear evidence the animals' habitats were tampered with and that they may have been taken.
On Monday afternoon, the zoo said two of their emperor tamarin monkeys were missing and that their habitat had been "intentionally compromised."
The zoo said emperor tamarin monkeys would likely stay close to home but that after searching near their habitat on Monday the animals were not located.
The Dallas Zoo said they notified the Dallas Police who are actively investigating a recent string of incidents at the zoo involving damaged habitats and animal escapes. According to the zoo, they have reason to believe the tamarins were taken.
Because the investigation into the animals' disappearance is ongoing, the zoo was unable to provide any other information about the missing tamarins or the unprecedented series of events that have focused national attention on the Dallas Zoo.
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It's the fourth suspicious incident at the zoo since the start of the new year -- the first involving a clouded leopard, Nova, who escaped her enclosure after police discovered it had been intentionally cut. As Dallas Police opened a criminal investigation, zoo staff members the next day found a similar intentional cut on the enclosure that houses langur monkeys, all of whom were accounted for.
Most recently, an endangered vulture was found dead with an "unusual wound," zoo officials said. Dallas Police later said they were investigating the death as being suspicious.