( CNN ) -- Police have arrested a couple and charged them with kidnapping in the apparent abduction of two Amish girls in upstate New York this week , authorities said late Friday . Stephen M. Howells II , 39 , and his girlfriend Nicole F. Vaisey , 25 , are being held without bond , according to the St. Lawrence County Sheriff 's Office . Federal charges are also a possibility . On Wednesday , an Amber Alert was issued after 6-year-old Delila Miller and her 12-year-old sister , Fannie , disappeared from a vegetable stand near their family farm in Oswegatchie , located about 50 miles from the Canadian border . A witness told police the girls were tending to a customer who drove up in a white 4-door sedan and then disappeared when the vehicle pulled away , according to the Amber Alert . The Amber Alert was canceled Thursday night after Delila and Fannie were apparently abandoned along a road in Richville , about 40 miles away . `` The children walked up to a home , knocked on the door of a stranger , '' St. Lawrence County District Attorney Mary Rain told CNN affiliate WWNY . `` The stranger brought them home to their house and police were waiting . '' She said the girls were `` a little wet and cold , '' but otherwise healthy . The investigation moved quickly on Friday , as `` good police work '' and tips from the girls led authorities to the suspects , said St. Lawrence County Sheriff Kevin Wells . `` We have two strong young girls , '' Wells said . `` The reason we 're able to make an arrest tonight is because of just how strong they are and things they 're able to remember . '' Two cars -- one white , one red -- were towed from the scene by authorities , affiliate WSYR reported . The house where Howells and Vaisey live is being processed for evidence , according to Wells . CNN 's Joe Sutton contributed to this report .
A man and his girlfriend are charged with kidnapping . The girls provide tips that lead police to the suspects . The girls were apparently abducted near their farm in upstate New York . They were apparently abandoned on a road a number of miles away .