The FBI searched the home of Isabella Hellmann Friday, a Florida mother who went missing on a boat trip with her husband in May. Hellmann’s husband, Lewis Bennett, said Hellmann vanished when their boat began taking on water, but the FBI’s search of the apartment shed new light her disappearance.

Bennett said he and his wife were en route to Key West from St. Maarten on May 15 when she disappeared. Bennett said he was below deck sleeping while his wife was on the boat’s deck keeping watch when the 37-foot catamaran struck an unidentified object. When he woke up to the boat taking on water and walked to the deck of the boat, Hellmann was missing, Bennett said.

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Hellman left the boat in a life raft as it sank. The Coast Guard picked him up about three hours later, but there was no sign of his wife. After an extensive, four-day search was called off, the Coast Guard and FBI said the case was now a missing person’s investigation.

"Friday’s all-day raid of Isabella Hellmann’s suburban Delray Beach condominium dispelled any idea that authorities are satisfied the woman’s vanishing was an accident," the Palm Beach Post reported.

About 20 FBI agents searched the Delray home Hellmann previously shared with Bennett Friday as part of the investigation into her disappearance, according to the Post. A neighbor told the Post that she and others were ordered to stay inside their homes as the FBI agents approached.

"One yelled that they had a warrant to search the place, and then they broke the [crime scene tape] to get inside," said Anne Fennimore, noting that she saw six crime scene technicians in latex gloves go inside.

An estimated eight and a half hours later, investigators exited the house with objects inside evidence bags. According to a police report obtained by ABC News, a federal investigator told the Boca Raton Police that Bennett was under investigation for Hellmann’s disappearance.

Hellmann’s sister Dayana expressed doubts about the nature of her disappearance shortly after it happened in May.

"He was calm,” she told WPTV of the first time she saw Bennett after Hellmann vanished. "He wasn’t crying or anything. When I saw him I ran to him and I hugged him and I said, 'Where is Isabella?' And he said, ‘I don’t know.'"

Hellmann and Bennett have a 10-month-old daughter together, whom Hellmann’s family is afraid Bennett will take back to Australia where he has dual citizenship. The two were married in February and had been together for four years after meeting online. Hellmann’s sister said she repeatedly questioned Bennett about her sister’s whereabouts after he returned from the trip.

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"'Why didn’t you stop the boat and drop the anchor to do something about it?'" she said. "And he said he needed to keep the boat on track, so his priority was to keep the boat on track. I asked him, 'Do you think she’s alive? Do you think she’s dead?' And he said, 'I think she’s sleeping.' That was his answer."