Authorities in Ohio have searched a wooded area near a casino after receiving letters suggesting they could find clues there connected to the disappearance of 5-year-old Dulce Alavez in September.

Dulce vanished from a park in Bridgeton, New Jersey, on September 16, and extensive searches of the area have not produced any significant leads into the circumstances of her disapperance.

NJ.com reports that police in Austintown, Ohio, searched a wooded area near a casino there on Friday, in response to letters sent to a public library and the Hollywood Gaming casino and race track in Austintown, which is about 70 miles southeast of Cleveland.

Sgt. Richard John of the Austintown police told the news outlet that investigators did not find anything during their K-9 search on Friday, and it is unclear if they will search the area again on Monday.

The law enforcement official reportedly said that letters sent to the casino and library indicated that Dulce may be in the area. He said the investigators were working to determine whether the letters were mailed or dropped off.

Bridgeton Police Chief Michael Gaimari did not appear to believe the tip was credible.

“There’s no reliability to the tip at this point,” Gaimari said, according to the NJ.com report. “There’s no information in the investigation that would lead us to Ohio.”

At a council meeting in January, the police chief reportedly said he was optimistic Dulce would be found alive.

“We are still optimistic that the child is alive and will remain that way, but I would say that we have made significant progress in the past four to five weeks on the matter,” Gaimari said, according to the report.

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