Searchers combing an area near Oak Beach found a pocketbook believed to belong to Shannan Gilbert, the New Jersey woman who was last seen in the area in May 2010, a law enforcement source said Tuesday.
The pocketbook was found during a search of a marshy area that had been underwater and inaccessible when it was previously searched, the source said.
Tuesday's hunt took place not far from where the remains of 10 people have been found in the past year. Suffolk police believe one person killed them.
A number of key investigators are now working on the assumption that Gilbert, 24 -- who had worked as a prostitute and came to the area to visit a client -- had wandered off that day into a tidal area and may have drowned, the source said.
Her disappearance triggered a search and a chain of events that grew into a hunt for a serial killer after a cadaver dog began finding bodies in the Gilgo Beach area last December.
Between Dec. 11 and April 11, the remains of eight women, a man and a female toddler were found dumped along Ocean Parkway.
Of those women, the five who have been identified worked as prostitutes. Three partial sets of remains were connected to women whose other body parts had turned up far away -- in Manorville and Fire Island -- as early as 1996.
Tuesday's discovery renewed anxiety for Gilbert's family, who said police have not alerted them of their finds.
"This is all news to me," Gilbert's sister, Sherre Gilbert of upstate Ellenville, said in a telephone interview Tuesday night. "This can't be happening right now. I don't understand why it took the cops a year."
Suffolk police declined to comment on what was found.
"At this juncture we have not found any human remains," Insp. Stuart Cameron, commanding officer of Suffolk police special patrol bureau, said Tuesday afternoon during a news conference.
"I'm not at liberty to discuss whether any significant items were found," he said.
The search, which lasted from 8 a.m. to 4 p.m., will resume Wednesday, Cameron said. Reeds were thick in the area, Cameron said, and Suffolk County public works crews and equipment would be on hand Wednesday.
Weather conditions since the area was last searched earlier this year, plus August's Tropical Storm Irene, might have changed conditions in the area, Cameron said.
Police had searched 90 "points of interest" along Ocean Parkway on Monday but said they found no evidence.
The search on Monday had focused on areas along the parkway that had been targeted for further searching based on high-resolution pictures the FBI took during an overfly in April.
Cameron said the unexpected resumption of the search was due to good weather. "This is not a result of any new tip," he said.
The remains of the 10 bodies have been found in the brush and heavy vegetation along Ocean Parkway.
Suffolk Police Commissioner Richard Dormer said last week that he does not believe Gilbert was killed by the person who killed the other victims.
Gustav Coletti, of Oak Beach, one of the last people to see Gilbert alive after she ran from another person's home to his, said he let the police into the gated community Tuesday about 8 a.m.
"They searched by the basketball court and the playground areas inside the Oak Beach Association," Coletti said.
Coletti, who had called police the night Gilbert disappeared, also said he saw Suffolk police with dogs search a marshy area behind a row of houses.
Tuesday night, police set up a checkpoint at the entry point of the stretch leading to the gated Oak Beach community, stopping cars and asking entrants for identification to verify they live there.