Discuss as:

Was call of distress about yacht explosion a hoax?

NBC New York

Emergency crews stage for rescues in yacht explosion.

Updated at 11:10 p.m. ET: Coast Guard officials suspended a search for a yacht that reportedly exploded off the New Jersey coast, leaving 21 people stranded on life rafts. Officials are now investigating the case as a hoax, according to a statement released late Monday.

An emergency radio transmission came in at 4:20 p.m., saying that the Blind Date, a motor yacht, had exploded 17.5 miles east of Sandy Hook. The caller said nine people were injured but that the 21 people aboard had been accounted for and were floating on life rafts. The caller was not able to provide the boat's precise location because the power had been cut.

Read original story on NBCNewYork.com

But after six hours, a large search effort yielded no hints of a yacht explosion, even though search conditions were ideal, with air and water temperatures in the 60s, Coast Guard spokeswoman Jetta Disco said. Seven aircraft, including helicopters and fixed-wing planes, and two Good Samaritan vessels had combed the area, Disco said.

"In any of these cases, especially when we are on the scene quickly and are unable to locate the reporting vessel, there is always the need to consider the possibility of a hoax," Coast Guard Lt. Joe Klinker told NBC News.

Disco said she did not know whether the yacht had a float plan, which is typical. She said that when she looked up the boat in a database, many vessels named Blind Date came up. 

Coast Guard and other state and local agencies responded to more than 60 suspected hoax calls in the northern New Jersey, New York City and Hudson River region in 2011.

Making a false distress call is a federal felony with a maximum penalty of five to 10 years in prison, a $250,000 fine and reimbursement to the Coast Guard for the cost of performing the search. 

NBC's Jonathan Dienst and msnbc.com's Isolde Raftery contributed to this report.

More content from msnbc.com and NBC News:

Follow US News on msnbc.com on Twitter and Facebook