The youngest of three suspects accused in the slaying of two Navajo homeless men told jurors Friday that he and his friends used cinder blocks and a wooden table leg to beat the victims before stabbing them multiple times.

The teen, now 16, took the stand for prosecutors in the trial of co-defendant Alex Rios, who faces two counts of first-degree murder and numerous other charges related to the killings.

The teen's testimony offered a chilling account of the July 2014 attack that led the city's mayor to establish a task force on Native American homelessness. The testimony was a condition of a plea agreement that offered the teenager the possibility of release at age 21.

The beatings followed a night of drinking and drug use at a house party, according to the testimony.

Sometime after the party, the three suspects went to a vacant lot nearby and began attacking three homeless men. One of them men was able to run away. The other two — Kee Thompson and Allison Gorman — were sleeping, with one of them on a mattress and the other on the ground.

One teen used a wooden table leg to beat the men, while the 16-year-old was handed a cinder block and began hitting one of the men with it repeatedly.

He testified that Rios, now 20, also hit one of the men.

"He picked it up over his head and slammed it," he said of how Rios beat the men with the block.

Rios' attorney has argued his client didn't participate in the attack and only watched from a distance, scared and in shock, as it unfolded.

One teen poured a pile of dirt on the face of one of the victims and also urinated on one of the men, according to the teen's testimony.

The teen said after about 30 minutes, the three went back to the house to get two knives, and all took turns stabbing the men.

"I stabbed the guy on the mattress seven times," the teenager said. "Alex stabbed the guy on the ground about the same amount of time as me."

About a half-dozen of the victims' family members listened to the testimony. Relatives wiped away tears as the boy answered the prosecutor's questions.

The defense began questioning the teen late Friday afternoon.