The New Jersey nurse who mysteriously toppled to her death off a Bermuda-bound cruise ship was trying to climb from one balcony to another when she slipped and fell into the sea, cruise officials and law-enforcement sources said Tuesday — a story her family doesn't believe.

An FBI official said that Mindy Jordan, 46, tried to climb over a railing to return to cabin No. 9560, which she shared with boyfriend Jorge Caputo, at about 7:20 p.m. on Sunday — less than four hours into the journey from New York.

Jordan fell into the water about 45 miles outside of Atlantic City, N.J.

The Pine Hill, N.J., woman's family said the pair had been traveling aboard the Norwegian Dawn with another couple. Jordan's mother, Louise Horton, said she had doubts about the cruise line's version of events partly because her daughter was in an abusive relationship with Caputo.

FBI officials were flying to Bermuda to meet the cruise ship, which docked early this morning, and begin their formal investigation, a source said. Caputo continued on with The Norwegian Dawn after Jordan fell overboard.

Her family expressed disbelief that the petite mom of two could have done something so reckless, and were puzzled by the cruise line's account of the incident.

"I don't believe it for one freaking minute," said Horton, 66, of Bordentown, N.J.

Jordan's sister, Julie August, called the story "crazy" and pointed to the fact that Jordan stood only 4-foot-10 and would have had difficulty climbing over a high railing.

"Not unless her room was on fire," she said. "She's not some partying kid on a cruise."

Several relatives were immediately suspicious of Caputo, 56, a service manager at a Nissan dealership in Cherry Hill, N.J., and accused him of abusing Jordan in the past.

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