A man accused of abducting Charlotte Sena, 9, from a New York state campground was identified after police matched a fingerprint on a ransom note left at the girl's home Monday morning – a break that led to the man's arrest and Charlotte's rescue after an exhaustive two-day search.

Police were monitoring the Sena family home when a person pulled up to the house and dropped the note in the mailbox, Gov. Kathy Hochul said at a news conference late Monday. Investigators around 2:30 p.m. matched a fingerprint on the letter to Craig Nelson Ross Jr., who was in a database from a 1999 DWI case.

Hours later, SWAT teams raided a camper where Ross, 47, lived behind his mother's home in Saratoga County, less than 20 miles from the state park where Charlotte vanished Saturday. "After some resistance," Ross was arrested, Hochul said.

Charlotte was discovered hidden in a cabinet and appeared to be physically unharmed and "in good health," Hochul said. She was taken to a local hospital, as is customary in such cases.

"We are overjoyed at the news that Charlotte Sena has been located safely this evening after an intense days-long search," the governor said in a statement. "Our hearts are with her family as they welcome her home."

In a statement shared with USA TODAY, Charlotte's aunt Jené Sena thanked law enforcement and the families and friends who volunteered in the search.

"We are thrilled that we are home and we understand that the outcome is not what every family gets," Sena said.

Ross charged with first-degree kidnapping; police searches continue

Ross was being held early Tuesday at the Saratoga County Correctional Facility without bail, according to New York State Police.

He was processed at New York State Police headquarters and then arraigned at the Milton Town Court on a felony charge of first-degree kidnapping. Additional charges were expected, police said.

An arraignment memorandum, obtained by USA TODAY, said Ross "wrote a ransom letter with intent to compel the payment of monies as a ransom" for Charlotte. The public defender's office, which is representing Ross, did not immediately respond to a request for comment.

Hochul, at the news conference late Monday, said "there are a lot of searches underway," including of a residence just 2 miles from the Sena family home. The governor added that it had not been determined whether Ross "is known to the family."

Hundreds of people assisted in the search for Charlotte

Ross' arrest concluded a two-day search that saw more than 400 people, including police, forest rangers and firefighters, descend on Moreau Lake State Park, about 35 miles north of Albany, New York, and the surrounding area. Helicopters, drones, dogs and water search teams covered more than 46 linear miles.

Charlotte, the middle child of three girls, disappeared Saturday evening while riding her bicycle on a loop trail around the cabin where she and her family were camping with friends over the weekend. Her family lives in Greenfield, a town of about 8,200 in Saratoga County, New York.

On Sunday morning, an Amber Alert including Charlotte's description was issued. Authorities said they suspected Charlotte had been abducted based on the circumstances of her disappearance.

While law enforcement continued its search and examined the ransom note, Charlotte's parents and siblings remained at the campsite surrounded by family and friends. The Sena family urged the public on Monday to look out for anyone who appeared suspicious or matched Charlotte's description and pleaded for tips to be sent to the New York State Police.

"It's still pretty overwhelming because all of us feared the worst," Hochul told reporters Monday. "Obviously it's a traumatic event for the family and certainly Charlotte, and we'll continue to keep them in our prayers as they heal."