SIOUX FALLS, S.D. (AP) — A South Dakota couple have pleaded not guilty to charges that they gave four children illegal drugs and zapped them with a cattle prod to get them to comply with orders.

Lance Long, 36, and Crystallynn Long, 40, of Sioux Falls, made their initial court appearances Monday. The Longs pleaded not guilty to several counts, including aggravated assault with a dangerous weapon, distribution of marijuana to a minor, distributing a controlled substance to a minor and abuse or cruelty to a minor, the Argus Leader reported.

Authorities with the Minnehaha County Sheriff’s Office said the alleged abuse had been going on for several years and involved boys ages 17, 13 and 11, as well as a 15-year-old girl. The children are related and some are half-siblings.

Authorities received a child abuse complaint May 13 from someone connected to the couple, Minnehaha County sheriff’s Capt. Josh Phillips said. The children were interviewed and the Longs were arrested after fleeing to Oklahoma.

The children are in the custody of the Department of Social Services.