CANTON, N.Y. (CBSNewYork/AP) — A northern New York couple accused in the kidnapping of two young Amish sisters may have also planned to abduct other children, authorities said Saturday.

St. Lawrence County Sheriff Kevin Wells said “there was the definite potential” of additional victims besides 7-year-old Delila Miller and 12-year-old Fannie Miller, who were returned to their family late Thursday.

Stephen Howells Jr. and Nicole Vaisey, both of Hermon, were arrested on Friday.

Police also said Saturday that the two sexually assaulted the victims.

Each was charged with two counts of first-degree kidnapping with the intent to physically harm or sexually abuse the girls. Wells said additional charges may be filed.

The sisters vanished Wednesday evening in Oswegatchie, touching off a massive search in the farming community near the Canadian border. They turned up safe Thursday night at the door of a house 15 miles from their home.

As CBS 2’s Dave Carlin reported, the sisters were released by their captors late Thursday in a secluded area.

Police say the girls gave investigators enough detailed information to lead cops to the couple and prevent more possible abductions and abuse.

The girls are among the youngest of Mose and Barb Miller’s 13 children, who range in age from 1 to 21 years, said neighbor Dot Simmons. The girls routinely took on the chore of selling the fruits, vegetables, jams and other products of the farm and had left the rest of their family during evening milking when they saw the car at the stand.

Wells said the motive was “to take these girls from their home and victimize these girls.”

St. Lawrence County’s District Attorney Mary Rain said on Friday that information provided by the girls helped lead authorities to Howells and Vaisey.

The neighbors of the suspects are shocked and angry, including one who regrets not paying more attention, Carlin reported.

“We kind of feel like maybe failed as neighbors because we didn’t see anything for 24 hours,” the neighbor said.

Howells and Vaisey do not have prior criminal records, Carlin reported.

Howells worked at a hospital and Vaisey was a pet groomer.

Both suspects are being held without bail.

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