PANAMA (CBS/AP) — Panamanian investigators say FBI agents are helping them search a Panamanian hostel for blood traces and other signs of a California woman last seen there several months ago.

Searches on land and off the coast have turned up no sign of 42-year-old Yvonne Baldelli of Laguna Niguel, Calif., whose family reported her missing in January.

Police investigator Alexis Munoz tells The Associated Press that his officers, FBI agents and forensic specialists are using a chemical that can reveal signs of blood on the walls and floor of the hostel El Sapo. The hostel is in the Bocas del Toro archipelago, a popular tourist spot where Baldelli was last seen Nov. 26.

Munoz says Baldelli was seen with an American boyfriend, who left for Costa Rica days later and has since returned to the U.S.

Officials call Brian Brimager, the former boyfriend who was traveling with Baldelli, as a “person of interest.”

Brimager claimed Baldelli ran off to Costa Rica with another man but her passport showed she never left Panama.

Baldelli’s family says Brimager returned home within weeks of Baldelli’s disappearance and got married to another woman.

The Baldelli family has set up a facebook page called “Find Yvonne Baldelli.”

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