By Steve Almasy and Chris Boyette, CNN

Isabella Hellman’s husband says he last saw her at 8 p.m. on May 14, 2017, hours before he made a distress call.

(CNN)A British man who is already in US federal custody will face a second-degree murder charge in connection with the disappearance of his wife, who went missing while the couple sailed through the Florida Straits last year, according to a criminal complaint.

Isabella Hellman was reported missing nine months ago after the Coast Guard received a distress call from her husband, Lewis Bennett.

Bennett, 41, was rescued from a life raft about 30 miles west of Cay Sal, Bahamas, an island near Cuba’s northern shore. The couple’s catamaran was not far away.

An FBI agent says in an affidavit filed Saturday that he believes Bennett intentionally scuttled the couple’s vessel late on May 14 or early May 15. The affidavit concludes, “There is probable cause to believe that … Bennett … killed Hellman.”

CNN reached out Tuesday evening to an attorney for Bennett, but didn’t receive an immediate response. According to court documents, Bennett was sentenced Tuesday to seven months in federal prison for transporting stolen gold and silver coins.

During the investigation, Bennett said that while he was asleep, the 37-foot catamaran hit something and was taking on water. He abandoned the vessel about 45 minutes later, court documents say.

When asked by the FBI what he did to find Hellman, Bennett “indicated he did not do anything” like call out for her or use flares to illuminate the water, the affidavit says. The document notes Bennett told other agencies he yelled for his wife and threw out a buoy.

Bennett, a dual citizen of the United Kingdom and Australia, told investigators he last saw his wife May 14 at 8 p.m., about five hours before his SOS call.

The Coast Guard said the life raft contained a number of Bennett’s items, including a suitcase, two backpacks and nine plastic tubes, “containing what were determined to be silver coins,” according to the affidavit. Authorities later said those coins were stolen.

The Coast Guard searched for Hellman, a 41-year-old real estate agent from Delray Beach, Florida, for three days.

A friend of Hellman’s told CNN last year the couple was on a vacation that included visits to St. Martin and Cuba.

“She was excited about the trip,” Tina Saragaglia said.

Hellman was a naturalized US citizen, court documents show. Her body has not been found.

Bennett has asked a Florida probate court to declare his wife deceased.

CNN’s Samira Said, Rosa Flores, Tony Marco and Dave Alsup contributed to this report.

IMAGE: Isabella Hellman’s husband says he last saw her at 8 p.m. on May 14, 2017, hours before he made a distress call.

For more on this story go to: https://edition.cnn.com/2018/02/20/us/florida-woman-missing-at-sea-husband-charged/index.html