A ransom note proved instrumental in the rescue of 9-year-old Charlotte Sena, who went missing Saturday night while on a family camping trip in upstate New York.
The note was placed in the mailbox of the family home — which was being guarded by state police — around 4:20 a.m. Monday.
Fingerprints on the ransom note were used to identify the suspect, 47-year-old Craig Nelson Ross Jr. Cell phone pings from the campgrounds were also linked to the suspect.
Ross was eventually tracked to a property with a home and a camper out back. His mother occupied the home, while Ross lived in the camper. Charlotte was found hidden in a cabinet inside the camper.
Charlotte was rescued and Ross was arrested.
"She knew she was being rescued. She knew that she was in safe hands," said New York Gov. Kathy Hochul at a press conference.
The suspect was still being questioned as of Monday night. Charges had not been brought as of Hochul's last update, "but they are fully expected," she said.
Hochul said Charlotte appeared "outwardly, physically unharmed," but was transported to a local hospital, as is customary.
Ross lived about 2 miles from Charlotte's home, but it has not yet been determined if he knew the family, or if the 9-year-old had been under surveillance for any length of time.
Hochul said it appears the suspect himself dropped off the ransom note.
"He literally drove up to the family's mailbox," said the governor.
He left a "critical piece of evidence behind — his own fingerprint," she said.
The search for the 9-year-old had been extensive. More than 100 people banded together to help find Charlotte, who had been bike riding at Moreau Lake State Park when she disappeared. Search efforts included law enforcement on the ground, drones, boats, dogs and an underwater rescue team.
"Our prayers have been answered," Hochul said, who had been providing updates on the case.
"We're overcome with relief and gratitude," she said.
An investigation remains ongoing, as officials are exploring whether Ross is connected to any other cases.
SEE MORE: New York authorities: Missing 9-year-old Charlotte Sena found safe
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