Updated

Panamanian police want to know more about an American ex-Marine named Sunday as a person of interest in the disappearance of a 42-year-old California woman last seen on an island near the Costa Rican border.

Police in Panama and the United States haven't identified Brian Brimager as a suspect as they investigate the case of Yvonne Baldelli, who was reportedly dating Brimager. But Panama national police official Alexis Munoz said Sunday that Brimager had raised investigators' interest.

Later in the day, Baldelli's mother, Lillian Faust, who is in Panama for the investigation, said she thinks her daughter is dead and begged for Brimager to tell what he knows about what happened to her.

"My husband, I, the famiy know that something happened to her. Some people want to say that she's out there somewhere, but everyone in the family knows that's not possible," Faust said.

"We did not want to accept it for a long time, but we have accepted it," she added.

Panama police said Brimager left Panama for Costa Rica and the United States some 10 days after last being seen with Baldelli in November on the Bocas del Toro islands. Baldelli's family reported her missing in January.

Munoz said witnesses at the hotel where the couple stayed reported they had a "violent" relationship and frequently fought and argued. Panamanian officials said Brimager was between the ages of 35 and 40 and had brought Baldelli to the islands.

On Thursday, FBI and Panamanian forensic investigators visited the hostel.

The mother said she had never met Brimager, who she thinks is from Southern California.

Faust said authorities had not told them that Brimager is suspected of anything. "I do not know, but if he knows something I would love for him to speak," she said.

Baldelli's sister, Michelle Faust, told The Associated Press on Wednesday that the missing woman had gone to Panama in September to design and produce clothing to sell on the islands' beaches.

She said the family had talked with the boyfriend after he returned to the U.S., but declined to give any details of what was said.

Munoz said Brimager had worked while in Panama as a performer in bars playing guitar and singing for tips.

Based on reporting by the Associated Press.

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