What started out as a day at the beach for Christina Roach and her family, quickly took an unexpected turn.

Last Sunday, Roach, her husband, and their nine children were swimming near the East Avenue boat launch, when they noticed a strange sighting.

"Before I knew it, I looked, and I was like, oh my God.  It's an alligator," said Roach.  "I was in shock because like everybody knows we are not supposed to have them."

After getting all of her kids out of the water, Roach grabbed her phone and began recording.

"I've gotten a lot of people saying it's probably fake," said Roach.  "I swear to God, it's not."

The video captures what Roach describes as a four to five foot alligator swimming in Lake Erie.

"He kept going under and then bobbing his head back up and swimming, like left and right, " said Roach.  "After a while, he actually like disappeared."

Roach says her family then called the Erie Police Department.

"We stayed for a  little bit, waited for the police to come and they didn't even believe us at first," said Roach.  "They had to come down and see for themselves."

Over the past week, the story has been picked up by multiple news outlets, gaining national attention.

"I didn't think it was going to be as viral as it has become," said Roach.  "It was crazy:"

The Erie Port Authority is investigating the sighting and has placed warning signs at the end of East Avenue.

"This has been very unique for us," said Erie Port Authority Executive Director Julie Slomski. "We're taking this very seriously and our team is being very, very diligent just to make sure we are keeping everyone safe."

Meanwhile, Roach is hoping for a positive outcome.

"I hope that he is found safely," said Roach.  "I don't want kids to be bit, dogs to be bit, or even the alligator harmed in any way.  Hopefully he is found."