DENVER — Leaders of a prison gang known as 211 Crew put out a “hit” against an El Paso county judge, sending him into hiding, as retaliation for his signing of warrants into the investigation of the murder of Colorado prisons chief Tom Clements.

A source familiar with the case told FOX31 Denver, Judge Jonathan Walker was placed under police protection after investigators learned about the threat to kill him.

A law enforcement source, who spoke on the condition of anonymity, tell FOX31 Denver Investigative Reporter Tak Landrock that an informant at the El Paso County jail told Gang Unit Detectives with the El Paso County Sheriff’s Office about the assassination order on Judge Walker.

The source spoke to FOX31 on the condition that they not be identified because they were not authorized to speak about the case.

“Investigators are taking this very seriously,” the source said.

Walker signed numerous search warrants against members of the 211 Crew, a white supremacist prison gang, allowing investigators to search phone records and homes of gang leaders looking for information into Clements death.

Clements was allegedly gunned down by Evan Ebel in March.

Ebel was a member of 211 Crew and may have conspired with other inmates to kill Clements, investigators have speculated. He was killed in a shootout with Texas deputies two days after Clements was murdered.

Clements earned widespread recognition for not only prison reforms but for a crackdown on prison gangs, including the 211s.

Investigators have said they were looking into whether Ebel might have conspired with other inmates to kill Clements.

In April, Thomas Guolee and James Lohr, both suspected members of 211 and associates of Ebel were arrested by El Paso County deputies.

Both Lohr and Guolee were wanted on warrants unrelated to the Clements case at the time.  However, at the time of their arrest, deputies said they wanted to question the men about Clement’s death.