Alligators have been mysteriously appearing in a river in Pennsylvania, despite not being native to the area.

The reptiles have been spotted swimming in the Kiskiminetas River near Apollo over the past several months.

In August, officials embarked on a weeklong search for an alligator that had found its way into the area, local outlet TribLive reported. The 4-foot-long reptile, nicknamed “Chomper” by police, was spotted by two kayakers who reported it to local authorities. Once the alligator was captured, he was brought to a reptile rescue organization, Nate’s Reptile Rescue .

Now, another alligator has been spotted swimming in the river. Six kayakers had been on the same stretch of water when they spotted the reptile.

“We got excited and paddled around to get better pictures of it,” one of the kayakers, Joshua Kelley, told TribLive. “We were kayaking and saw an animal and thought it was a muskrat, but realized it was an alligator.”

The kayakers tried to approach the lost reptile to no avail. Once they were back on land, Kelley called the local police about the incident.

Shelby Mitchell, Kelley’s fiancee who had also been kayaking at the time, also saw the alligator lurking in the river.

“I definitely think someone released their poor pets into the river,” Mitchell told the news outlet. “I feel bad for the poor guy.”

Alligators’ preferred habitat is freshwater rivers. They are native to Florida, Louisiana, Georgia, Alabama, Mississippi, the Carolinas, Texas, Oklahoma and Arkansas. However they are certainly not native to Pennsylvania.

It is not certain whether the alligators will be able to thrive in this part of the U.S, as it depends what food sources are available as well as the conditions of the river.

It is not certain how the alligators got there, but TribLive reported that Chomper had likely been placed in the river by someone on purpose. It is likely the same case with the other alligators.

Some people keep alligators as pets. But they can prove tricky to keep, as they need a lot of space and can be aggressive when provoked.

Alligators do not typically hunt or hurt people, but they are extremely territorial animals. This means that conflicts can occur, especially if a person is not aware of their presence. As these alligators are in an area where people will not expect them, this could pose a danger.

These recent alligator sightings are only two of several that have occurred in the state this year, TribLive reported.

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