BOISE, Idaho — Jurors cringed, cried and some desperately looked away as they were shown a series of deeply disturbing and graphic videos taken by a convicted child killer as he tortured, sexually abused and nearly killed a 9-year-old boy.

Federal prosecutors showed the video as part of their efforts to persuade the jury to recommend the death penalty for Joseph Edward Duncan III. He kidnapped the boy, Dylan Groene, and his sister, Shasta, in May 2005 after murdering their older brother, their mother and her fiance. The two young children were taken deep into the Lolo National Forest, where they endured weeks of horrendous abuse at the hands of Duncan.

Duncan ultimately shot the boy point-blank in the head while his sister, then 8, watched. He was arrested after returning to Coeur d'Alene, where a waitress recognized Shasta as the two ate at a Denny's restaurant.

The videos and photos taken at the cabin show Duncan forcing the boy to perform a sex act, whipping him with a belt and hanging him with a wire noose until the boy passed out.

"The devil is here, boy, the devil himself. The demon couldn't do what the devil sent him to do so the devil came himself," Duncan yells in one video. "The devil likes to watch children suffer and cry."

Duncan covered his face as parts of the video were shown, and jurors frequently shot him looks. Two of Duncan's standby attorneys also avoided looking at the screen.

Duncan, a convicted pedophile originally from Tacoma, Wash., has pleaded guilty to federal and state counts including murder. The federal jury is considering the death penalty on charges related to the kidnappings and Dylan's murder, but he also could face execution on state counts in the other three killings.

After releasing Dylan from the noose, Duncan promised to take him to the hospital so his injured neck could be treated. He also promised to tell hospital staffers where to find Shasta, who had been left back at the campground, so they could come find her. He kept neither promise.

After that, Duncan offered to let Dylan watch the video of his "death," then wandered away from the camera where he could be heard singing part of the Lord's Prayer.

After the video was shown, prosecutors called a man to the stand who testified that Duncan had raped him at gunpoint in 1980, when the man was just 14 years old.

Parts of the story seemed similar to some of Duncan's videotaped abuse of the Dylan. Once that testimony was over, the judge called a recess to give jurors a break from the violent material.