PALATKA, Fla. -- Putnam County investigators said they searched an area identified as Haleigh Cummings' grave in a letter dropped off at the St. Augustine Record last week, but the tip did not lead to the 6-year-old girl who has been missing for more than seven months.

"The tip was about a burial site and had actual directions," Capt. Dick Schauland said.

Schauland said the place mentioned in the letter had been searched before, but they returned with cadaver dogs and found no trace of a body or a grave.

"The information did not pan out on the tip, as has been the case on the last 4,000 or tips that we've had," Schauland said.

The letter, signed only with initials, was dropped off at the St. Augustine newspaper office last Wednesday afternoon. Associate Editor Richard Prior, who saw the letter, told Channel 4 the tip would lead investigators to Haleigh -- "if it's authentic."

The woman who dropped off the letter came forward, but investigators said she told them she was the messenger for a man who claimed to be an FBI informant with special psychic abilities.

Detectives were told the woman does not personally know the family or have any information about Haleigh's whereabouts. They would like to talk to the man who wrote the letter.

Haleigh disappeared sometime the night of Feb. 9 or morning of Feb. 10 from Ronald Cummings' mobile home in Satsuma. She and her younger brother were being watched by Misty Croslin -- at the time Ronald's 17-year-old girlfriend -- while the father worked a night shift.

An Amber Alert was issued the next day as investigators believed Haleigh was taken from the home. Investigators have given polygraph tests to everyone who had contact with Haleigh in the days before she disappeared and have followed leads throughout Florida and beyond, but they said they still don't know what happened to Haleigh.

"It's a roller-coaster ride, that's for sure. We just have to keep the faith," Haleigh's paternal grandmother, Teresa Neves, said on Monday. "Somebody somewhere knows something, you know. One day, and I feel like it will be very soon, somebody will give us a tip that will bring Haleigh home."

Anyone who has any information about what happened to Haleigh is asked to call Crimestoppers at 888-277-8477.