A Dakota Access Pipeline protester who locked himself to equipment at a worksite during the early months of protest has been charged with seven felonies related to an alleged knife attack.

Dale American Horse Jr., 28, is charged with three counts of reckless endangerment and two counts each of terrorizing and aggravated assault. Courts documents say he attacked a couple sleeping in a bedroom with their 6-year-old daughter around 9 p.m. Tuesday at a residence on the 4600 block of Lewis Road Northwest in Mandan.

American Horse was reportedly "extremely upset for an unknown reason" and allegedly began swinging the knife. He allegedly stabbed the man and woman to the extent they both needed stitches, according to court documents.

One of the man’s wounds on his arm was reportedly down to the bone. The woman’s fingers were also injured.

Mandan police responded to the incident, detaining American Horse at the scene and reportedly finding blood throughout the home.

American Horse was arrested and is held at the Burleigh-Morton County Detention Center, pending $7,000 cash bond.

His preliminary hearing is set for Feb. 26 at the Morton County Courthouse.

On Aug. 31, 2016, he spent six hours locked to a digger at a DAPL worksite along State Highway 6. He was one of eight people arrested at the protest.

His criminal charges related to that day have since closed, resulting in misdemeanor convictions for reckless endangerment and disorderly conduct, settled as yearlong deferred impositions of sentence.

Reach Jack Dura at 701-250-8225 or jack.dura@bismarcktribune.com.