Five teenagers and a 20-year-old man have been indicted in the death of an Arizona 16-year-old boy who was found badly beaten outside a Halloween party last year, the Maricopa County prosecutor said.
The beating of Preston Lord, 16, who died two days after he was found on a road in Queen Creek on Oct. 28, prompted calls for more police action against group violence by teenagers in that and other nearby cities.
Officials announced four indictments Wednesday, and two additional indictments were announced the following day. Police said the investigation was ongoing and there was more work to do.
William Owen Hines, 18, and Dominic Turner, 20, and two 17-year-olds have been charged with first-degree murder or, in the alternative, second-degree murder, as well as kidnapping, Maricopa County Attorney Rachel Mitchell said. Turner is also charged with robbery, she said.
The first four indicted in Preston’s death are being charged as adults, Mitchell said.
A 19-year-old, Taylor Sherman, was indicted Thursday with the same murder charge along with kidnapping. Another 17-year-old was also charged Thursday on a murder charge as well as aggravated robbery and kidnapping.
NBC News is not naming the 17-year-olds because they are minors.

Mitchell called the investigation “extremely complex” and said it involved thousands of pages of police reports and around 600 videos.
Preston was found in a roadway at 9:49 p.m. Oct. 28, police said, after officers had previously been dispatched to the area for a reported juvenile disturbance. He was taken to a hospital and died two days later.
At the time of the earlier call, at 9:07 p.m., officers saw a large group of juveniles leaving but observed no illegal activity and went to another call, police have said.
Last month, the medical examiner delivered a final report that ruled Preston's death a homicide. Authorities have not released a cause of death.
The criminal cases did not appear to be in online Maricopa County court records, and it was not clear whether any defendants had attorneys who could speak on their behalf. An attorney for Hines in two other cases said he did not represent Hines in the murder case.
“We extend heartfelt gratitude to the community members who stepped up to provide information to secure these arrests," Preston's parents, Nick Lord and Autumn Curiel, said in a statement distributed by their lawyer.
"But for law enforcement’s collective efforts and community members’ invaluable cooperation, these arrests would not have happened," they said. "Each arrest represents a step toward accountability and justice for our son Preston."
An investigative grand jury has been reviewing the case since Feb. 7, Mitchell said.
Following Preston's death and other assaults, police in the neighboring city of Gilbert have been looking at past cases of teenage group violence, including a gang investigation into a group called the “Gilbert Goons.”
Gilbert Police Chief Michael Soelberg and other officials did not say that any of the four are associated with such a group.
There are 12 active investigations into group teen violence in Gilbert, Soelberg said Wednesday after the indictments in the Lord case were announced.
Hines has criminal cases against him in Gilbert as an adult: three aggravated assault cases, two of which allegedly happened earlier but were not reported until December and January, Soelberg said.
Anger in the community over Preston’s death prompted a kind of online vigilantism, Soelberg said in January, with misinformation about people not connected to the case being posted online.
A 17-year-old was falsely accused of being a murderer and threatened because someone posted the wrong address online, Soelberg said then.
That behavior has continued, Mitchell said.
“To all of those who have continued to post innumerable, unfounded, ill-informed theories on social media: I hope you will pause and consider and evaluate the effect that you may have had on this family over the past several months,” Mitchell said.