"I think what we're trying to determine is whether a crime took place," said agent Jim Margolin of the FBI's New York office.

In a statement yesterday, the Norwegian Cruise Line characterized the disappearance as an accident. The cruise line did not name the woman, but her family identified her as Mindy Jordan of Pine Hill.

"Initial reports indicate that the 46-year-old woman was attempting to climb from one exterior balcony on deck nine to the adjoining balcony and subsequently fell overboard," the statement said.

Jordan and her boyfriend, Jorge Caputo, were traveling with another couple on the Norwegian Dawn, which left New York on Sunday for Bermuda, said Jordan's mother, Louise Horton.

The couples were staying in adjoining rooms, she said, but the cruise line did not say if Jordan was climbing between the two rooms.

Horton, of Bordentown City, said she wanted a full investigation. "The pieces just don't add together," she said in an interview yesterday morning.

Margolin said he did not know how the cruise line had reached its initial conclusion. "I don't know who their people spoke to," he said.

FBI agents will talk to cruise-line security personnel and any "pertinent witnesses," Margolin said, but he could not be more specific.

Caputo and the other couple were still on the ship yesterday, said Steve Lynn, Jordan's brother. He said that he did not know Caputo well, and that he and his mother did not know the other couple.

The Norwegian Dawn left the Manhattan Cruise Terminal at 4 p.m. Sunday, and Jordan was reported to have fallen overboard around 7:50 p.m., when the ship was about 45 miles northeast of Atlantic City.

The Coast Guard launched rescue helicopters from Atlantic City and Cape Cod in Massachusetts and searched for seven hours across 59 square miles, Petty Officer Christopher Evanson said.

The Norwegian Dawn also threw life rings into the water and deployed a small boat with rescue personnel, he said.

Gale-force winds and heavy seas hampered the search, which was suspended around 4 p.m. Monday, Evanson said.

The Coast Guard released the ship several hours after Jordan went overboard. The Norwegian Dawn is scheduled to arrive in Bermuda today.

The Coast Guard also is conducting a "marine casualty investigation" to determine what role - if any - the ship may have had in the death.

Horton, 66, last spoke to her daughter Sunday, when Jordan called to wish her a happy Mother's Day.

She called again before the ship left the terminal to say how pleased she was to get Mother's Day text messages from her own children, a 15-year-old daughter and an 18-year-old son, Horton said.

The next morning, Caputo called to say her daughter was dead, Horton said.

Jordan, a licensed practical nurse, had been living with Caputo. Lynn said the two had been dating for more than two years.

Horton said that she did not believe her daughter would have climbed around the side of the ship and that she had received conflicting accounts of how her daughter accidentally fell.

"She was so super-excited about this trip," Horton recalled. "Trust me: She was not suicidal."

Lynn said late yesterday that the family had not received any updates. And to its dismay, it learned of the cruise line's statement from reporters.

"We've not heard anything, and we're actually very frustrated about that," he said.