CONCORD, N.H. — A New Hampshire man was arrested Monday and charged with kidnapping 15-year-old Abigail “Abby” Hernandez after she left Kennett High School in Conway more than nine months ago.

Nathaniel Kibby, 34, was arrested without incident at his home in a trailer park in Gorham, New Hampshire, about 30 miles north of where the girl lives, and was charged with felony kidnapping, authorities said.

Police say Kibby knowingly confined Hernandez, then 14, on Oct. 9, sometime after she left school to walk to her home in North Conway. She returned home on the night of July 20, but authorities have not explained the circumstances of her return.

Attorney General Joseph Foster said Monday that law enforcement officials have worked around the clock to determine the facts surrounding the girl’s disappearance and return. He said Hernandez told police details that led to Kibby’s arrest.

Hernandez was held in a locked storage container behind Kibby’s trailer, a neighbor and friend of the girl’s told New England Cable News.

Kibby is scheduled for arraignment Tuesday in Conway District Court. It was not immediately known if Kibby has a lawyer. Foster said he will have a media briefing after the arraignment.

Senior Assistant Attorney General Jane Young, who heads the criminal bureau, would not say what Kibby does for a living or describe his background. She said details would come out in court Tuesday.

A phone number associated with Kibby was not in service.

In an interview earlier on NBC’s “Today,” Hernandez’s mother, Zenya Hernandez, said that when her daughter returned home, she was thin and pale and had “a look in her eyes I’ve never, ever seen before. And that’s something that’s haunting me, and I think will haunt me for the rest of my life.”

The girl also issued a statement, which was posted on Facebook, thanking people who searched for her and saying she believes their hopes and prayers “played a major role in my release.”

Zenya Hernandez said she believes that Abby did not run away from home and didn’t know the man who is believed to have driven off with her. Last week, police released a sketch of him based on the girl’s description. The mother also said that rumors that her daughter was pregnant aren’t true.

Young said that when the girl disappeared, she apparently had no way to get about or secure food, shelter or other necessities. She said Hernandez “went dark” and could not be traced through social media for the duration of her absence.

However, police revealed several months ago that she had written home to her mother. When the letter surfaced, FBI agent Kieran Ramsey said it was possible the girl had run away, but someone could be coercing her into staying away. Police have not revealed the contents of the letter.

Neighbors said Kibby kept a low profile.

“He seemed to be nice, down to earth. He was very polite,” said Roger Lawrence, 66, who lives in the same mobile home park as Kibby.

Lawrence said they met last summer while Kibby was walking his dog and exchanged pleasantries. He said he didn’t see Kibby all winter, but saw him Saturday, walking past his home to get his mail.

Lawrence was shocked to hear of the arrest.

“No words can explain it. I was ready to wring his neck,” he said. “I was wondering what happened to that little girl myself, seeing it on the news, thinking, ‘Where could she have gone?’ ”

Another neighbor, Raylene Beaulieu said she had not seen Kibby during the time the teenager was missing and had not seen him much before then.

“He pretty much kept to himself,” she said.

She was surprised to hear of his arrest.

“I can see his trailer from mine, and I had no idea,” she said.

Donald St. Germain, 76, lives three trailers from Kibby’s, but never got to know him well.

“The only time I saw him was this spring when he had to fix the roof on his trailer,” St. Germain said.

Around noon Monday, St. Germain noticed police in the mobile home park. He was later interviewed by FBI agents, he said.

Police still had both ends of Kibby’s street blocked off hours after the arrest.