When two sisters, ages 13 and 15, disappeared from their Binghamton, New York home last year, authorities feared the worst. But 11 months later, Shaeleen and Ky-Lea Fortner were found alive and healthy in a town approximately ten miles away.

New York State police have arrested 29-year-old Amanda Hellman on second-degree kidnapping charges after the girls—now 14 and 16—were found at her house on Wednesday. Authorities entered Hellman’s home following a telephone tip regarding the girls’ whereabouts. The sisters, who were originally reported as runaways, were prevented from returning home for nearly a year, police say.

Shaeleen and Ky-Lea had last been seen waiting for a school bus in April, heading home after classes on a Monday afternoon. Police believe Hellman abducted the girls before they made it to their house.

“During the course of the next 11 months, Hellman, who is not related to either child, conducted numerous acts to prevent law enforcement from returning the two children to their foster parents,” a police complaint obtained by the Binghamton Press & Sun-Bulletin reads.

Reached by phone, police declined to describe Hellman’s relationship with the girls, other than as a “family acquaintance of the victims,” both of whom lived with a Binghamton foster family.

“The defendant and the two girls knew each other. That’s the most detailed I can give,” Broome County District Attorney Steve Cornwell said in a Thursday press conference.

A neighbor told the Daily Beast that he had not seen the girls during the time they were allegedly kidnapped, but that they had played in the neighborhood when they were younger.

“I never saw them, so it was quite a shock,” neighbor Fred Brooks told the Daily Beast. “The girls [Shaeleen and Ly-Lea] used to play with the girls next door, but that was prior to when they say they were kidnapped.”

But authorities do not believe the girls voluntarily stayed at Hellman’s home for the 11 months they were missing.

“The allegation is that they were kept in the defendant’s house without their consent or will to be there,” Cornwell said.

State police searched “every single day” of the girls’ absence, following a number of false leads before finally receiving a phone call that lead them to Hellman’s house Wednesday night, Cornwell said. He would not answer whether the girls had been mistreated or injured during their captivity, only stating that they were in good health and currently in the custody of Child Protective Services.

“Everyone should know that the two girls are safe,” Cornwell said Thursday night. “The investigation was expansive and they never stopped looking for these two teenage girls.”

Hellman, who was alternately seen crying and flashing the “rock on” sign as police lead her into jail, has pleaded not guilty to her felony kidnapping charges. She is being held without bail in Broome County jail.