A fourth Army Ranger, Luke E. Sommer, who has a dual U.S.-Canadian citizenship is under house arrest in his mother's home in Peachland, B.C., and fighting extradition to the United States. 

Blum, who pleaded guilty to conspiracy to commit armed bank robbery and brandishing a firearm during and in relation to a crime of violence, is scheduled to be sentenced by U.S. District Judge Franklin D. Burgess on June 8. Byrne, who pleaded guilty to conspiracy to commit armed robbery, is scheduled to be sentenced on June 1.

According to court documents, Sommer recruited Palmer, Blum and two men from Canada, Tigra Robertson and Nathan Dunmall. Blum was recruited to drive the getaway car. Byrne was identified in court documents as a "consultant" for the Aug. 7, 2006, robbery.

Byrne was not present at the robbery, the U.S. attorney said, but he advised Sommer to abandon his original plan to rob a casino and identified the bank as a potential target. Byrne also drove Sommer, Robertson and Dunmall to the bus station to catch a bus to Canada.

"While driving to the bus station, Sommer told Byrne that robbing the bank was more thrilling than combat and said he could not have organized the robbery without Byrne's help," the U.S. attorney said.

Blum drove the getaway car -- his own -- during the robbery, according to prosecutors. The robbers had removed the rear license plate of the car but didn't remove the front one. A witness jotted down the license plate number and authorities traced the car to Blum.

Searches at the Army base near Tacoma turned up body armor and money from the bank in the barracks rooms of Blum and Chad Palmer, a fellow Ranger. In Sommer's room, investigators found body armor, $10,000 in cash, two AK-47s and two semiautomatic handguns.

Blum was arrested in Greenwood Village while visiting his family.

Robertson is scheduled for a change of plea hearing on March 12. Sommer and Dunmall are fighting extradition from Canada.