WESTBROOK, Maine — Westbrook police issued warnings and began a search Thursday afternoon after receiving a “credible” report that a snake “as long as a truck and [with] a head the size of a small ball” was slithering along the riverbank near the playground of a local park.

The Westbrook animal control officer was unable to turn up such a snake — which would be unlikely to be indigenous to Maine — but the department said that it could have been an escaped pet and warned the public not to approach it if they spot it.

The snake was reportedly sighted in Riverbank Park, but no one enjoying the late afternoon sun seemed disturbed by the possibility of its existence.

“That’s kind of unbelievable, a snake of that size,” said Barry Pocock of Standish, while his three grandchildren played nearby. “There’s just no way.”

Westbrook Police Capt. Steven Goldberg said that the department had received only one report, but there was no evidence to suggest it was a hoax. The officers will continue to periodically check the park, he said.

Maine is one of 14 states that require the owners to acquire a permit for exotic pets, according to Born Free, an animal rights advocacy group.

Rose Welch was glad that the police were taking the report seriously, but didn’t want to see them go overboard.

“I just think there should be a public service announcement. I don’t think they should have to dredge the water,” Welch said, as she sat with her 8-week-old puppy on the riverbank where the massive snake was allegedly seen.

The Westbrook Police Department can be reached at 854-0644.