The U.S. Coast Guard is investigating the possibility that a distress call about missing boaters Saturday was a hoax.

The Coast Guard launched an extensive 22-hour search after receiving a series of short distress calls late Saturday morning from a man who said his boat had capsized and his three children were in the water off the coast of Kennebunkport.

The search, which covered more than 1,500 nautical square miles and involved hundreds of people, was suspended Sunday morning. The Coast Guard has not received any reports of missing people and hasn’t found debris from a vessel.

#BreakingNews @USCGNortheast releases audio of mayday call from missing man 10NM off of Kennebunkport, Maine #SAR #CoastGuard pic.twitter.com/qdw1eyTkYm

— USCGNortheast (@USCGNortheast) October 5, 2019

On Tuesday, Coast Guard officials said they are trying to determine if the distress call was a hoax.

“We are asking the public’s assistance in determining the source of the calls and the nature of the distress,” said Capt. Brian Lefebvre, commander of Coast Guard Sector Northern New England. “Additional information may aid in our closure of the case and offer a degree of finality to the many rescuers who dedicated their time and effort toward this search effort.”

Despite being asked, the man making the radio report did not identify himself or his vessel, according to the Coast Guard.

The Coast Guard released an audio clip of the distress calls Saturday in the hope that someone might be able to identify the caller’s voice.

The first in a series of distress calls was received around 10:30 a.m. on Saturday. A man says his 14-foot Jon boat was capsizing with three children on board. Jon boats are flat bottomed with two or three bench seats. They are typically used for fishing or hunting on inland waters.

The Coast Guard said the vessel was reported to be 10 nautical miles off the coast of Kennebunkport.

The man calmly says during the distress call that the boat has flipped over and that he is going to try to get the children on top of the boat. If he is unable to get the kids onto the top of the boat, the man says, “We’re all just going to huddle in the water.”

Before losing his radio connection with the Coast Guard, he said all occupants of the boat had life vests.

Anyone with information about the distress call is asked to call 207-741-5478.