MIDDLETOWN, Conn. -- Police have searched the home of a woman who went missing at sea during a fishing trip with her son and is presumed dead.

Officers were seen removing bags, envelopes and boxes from 54-year-old Linda Carman's home in Middletown on Thursday night. They have said they are investigating "the facts and circumstances" surrounding her disappearance.

Local police and officers from South Kingstown, Rhode Island, conducted the search.

Carman and her 22-year-old son, Nathan Carman, left a South Kingstown marina on Sept. 17. Nathan Carman was found alone in a life raft by the crew of a passing freighter on Sunday about 100 nautical miles south of Martha's Vineyard, Massachusetts. He told the Coast Guard their 31-foot-long boat sank and he doesn't know what happened to his mother.

Linda Carman's disappearance is being investigating by local, state and federal officials in Rhode Island, Connecticut and Vermont.

A lawyer representing Linda Carman's three sisters said Friday the family is grateful for the efforts of the rescue team.

"As we continue our search for answers, the family has faith that our state and federal investigators are bringing maximum resources to bear, so that the family can have some degree of closure and an opportunity to heal," said Daniel Small, the Boston-based attorney.

Police searched Nathan Carman's home in Vernon, Vermont, on Monday and seized a modem, a cellphone SIM card and a letter. A search warrant indicated investigators think he was handling some boat motor repairs himself and the vessel might not have been seaworthy.

The case also has placed renewed attention on the unsolved killing of Linda Carman's father and Nathan Carman's grandfather, John Chakalos, a wealthy real estate developer found shot to death in his Windsor home in 2013. Court documents show Windsor police applied for an arrest warrant charging Nathan Carman with murder but a prosecutor didn't sign the warrant and asked for more information.

Nathan Carman has denied having anything to do with the killing, saying he was very close to his grandfather.