ALBANY, N.Y. (AP) — Federal authorities have filed additional charges against a northern New York couple accused of kidnapping and sexually abusing two young Amish sisters.

U.S. Attorney Richard Hartunian said Wednesday the case against Hermon residents Stephen Howells and Nicole Vaisey now involves six child victims. The couple had previously been charged with crimes against three, including the Amish girls, who were held for a day and released.

The new 21-count indictment hadn't been filed as of early Wednesday evening, but the prosecutor says the couple face charges they exploited three children between September 2013 and August 2014. Howells is additionally charged with six counts involving four children at other times.

Howells also is charged with five new counts of possessing child pornography.

Howells and Vaisey previously pleaded not guilty. Vaisey's lawyer won't comment. Howell's can't be reached.

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