A white supremacist prison gang member and an accomplice were in custody in the US state of Idaho after a brazen attack to free the inmate as he was being transported from a Boise hospital, authorities said.

Escaped inmate Skylar Meade, a 31-year-old member of the Aryan Knights gang, and his accomplice Nicholas Umphenour fled the scene early Wednesday morning and were arrested 2pm on Thursday in Twin Falls, authorities said.

Police throughout the region were looking for both men.

Meade was sentenced to 20 years in prison in 2017 for shooting at a sheriff’s sergeant during a high-speed chase.

Authorities said they were alerted of the attack at 2.15am on Wednesday as Idaho Department of Corrections officers prepared to bring Meade back to prison from Saint Alphonsus Regional Medical Centre in Boise, where they had taken him after he injured himself, officials said.

Meade had been imprisoned at Idaho Maximum Security Institution in Kuna, about 12 miles south of Boise.

Police said Nicholas Umphenour is suspected of shooting two corrections officers during Wednesday’s ambush in the ambulance bay at Saint Alphonsus Regional Medical Centre.

Hospital Shooting Inmate
Nicholas Umphenour, who has been identified by police as the man suspected of shooting prison officers at a Boise hospital (Boise Police/PA)

A warrant with a two million US dollars bond has been issued for his arrest on two charges of aggravated battery against law enforcement and one charge of aiding and abetting an escape, police said.

He and Meade drove off early on Wednesday after the shooting in a grey 2020 Honda Civic with Idaho plates.

The car was later located near Leeland, Idaho.

Officials described Meade, 31, as a white supremacist gang member.

Three prison officers were shot and wounded during the attack, two allegedly by Umphenour and one by responding police.

One officer shot by the suspect was in critical but stable condition, police said, while the second wounded officer had serious but non-life-threatening injuries.

The third injured officer also sustained non-life-threatening injuries when a responding officer, incorrectly believing the gunman was still in the emergency room and seeing an armed person near the entrance, opened fire.

“This brazen, violent, and apparently coordinated attack on Idaho Department of Corrections personnel, to facilitate an escape of a dangerous inmate, was carried out right in front of the Emergency Department, where people come for medical help, often in the direst circumstances,” Boise Police Chief Ron Winegar said in a written statement.

The Aryan Knights formed in the mid-1990s in Idaho’s prison system to organise criminal activity for a select group of white people in custody, as well as outside prison walls, according to the US attorney’s office in the district of Idaho.

In 2021, a man described as a leader in the group was sentenced to life in prison for his role in a plot to traffic drugs behind bars and use violence to collect unpaid debts.

In a court filing ahead of Harlan Hale’s sentencing, federal prosecutors described the Aryan Knights as a “scourge” within the state’s prison system that drains its resources.

“The hate-fuelled gang engages in many types of criminal activity and casts shadows of intimidation, addiction, and violence over prison life,” prosecutors wrote.