The stepfather of Celina Cass, an 11-year-old girl who has been missing for a week, was taken to the hospital in an ambulance on Monday morning.

Local New Hampshire news station WMUR reported that Wendell Noyes was suffering from "some sort of medical problem" and was taken to Upper Connecticut Valley Hospital after being carried to an ambulance on a stretcher. No further details were given.

In 2003, Noyes was forcibly committed to a hospital with a diagnosis of schizophrenia, ABC News reported. ABC obtained court records showing that Noyes has an arrest record for violating a restraining order and threatening his ex-girlfriend.

Celina's biological father, Adam Laro, spoke out for the first time on Sunday, pleading for his daughter's safe return. Laro was reportedly in the hospital when Celina disappeared, but has since been released.

"Whenever you want to come home, Celina, Daddy will be here waiting for you," Laro told CNN.

Celina Cass was last seen on the evening of July 25 in her West Stewartstown, N.H., home.

WMUR reported that Celina's mother and stepfather told authorities the girl was gone when they went to wake her up the following morning.

The FBI is offering a $25,000 reward for anyone who provides information that leads to Celina's whereabouts or an arrest in her disappearance. A private citizen has offered an additional $5,000 reward.

"We are still aggressively, aggressively searching and hoping to bring Celina Cass home," FBI Supervisory Special Agent Kieran Ramsay said in a news conference on Saturday.

Authorities have increasingly intensified efforts to locate Celina since her disappearance, and residents of West Stewartstown -- which has a population of about 800 -- have banded together to assist a frantic search for the schoolgirl, who is described as "shy" and unlikely to have run away.

In addition to the FBI, the Royal Canadian Mounted Police joined the search effort last week, and on Friday the Connecticut River was lowered to aid in a helicopter search for evidence of Celina's whereabouts. Divers searched unspecified bodies of water on Sunday.

The home that Celina Cass shares with her mother, sister, and stepfather is a mile from the Canadian border.

The Boston Herald reported that police officers were seen on Wednesday taking photographs of the interior of a red pickup truck parked across the street from Celina's home. Officers moved official vehicles in front of the pickup truck to obstruct media photographers' attempts to capture images.

Celina's mother and stepfather have not made a statement since their daughter disappeared.

Fox News reported that an Amber Alert hasn't been issued because the circumstances don't meet the state's criteria. "They have to have some specific information they're asking the public to look out for, usually a description of a car, or a license plate number, or something tangible," said Jim Van Dongen, spokesman for the Division of Homeland Security and Emergency Management, who isn't directly involved in the case.

"It just doesn't say, 'be on the lookout.' It's got to be something specific."

Officials told ABC News that the disappearance is still being treated as a missing persons case.

"Every house, every individual in the neighborhood is being spoken to," New Hampshire Assistant Attorney General Jane Young said Thursday.

Those who knew Cassie believe the girl wouldn't have run away.

"She never went anywhere without her mom or sister," family friend Rebecca Goodrum told the Boston Herald during a candlelight vigil Wednesday night.

"She is very shy," added Kayla Baglio, 18, who also knew the girl. "If she doesn't know you, she'd look at her sister to see if it was OK to talk to you."

Celina is 5-foot-5 and weighs 95 pounds, with long brown hair and hazel eyes and was last seen wearing a pink shirt, a pink pullover, blue shorts and shoes.

Any information about Celina Cass' whereabouts should be directed to New Hampshire State Police at 603-846-3333.

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