Derek Skyler Brux pleaded guilty in federal court in Casper on Tuesday to stealing a train on Oct. 9.

"I ended up getting upset, stole two locomotives and got on the main line," Brux told U.S. District Court Judge Scott Skavdahl during the change of plea hearing.

"I disabled two switches," he added.

During the hearing, Brux was polite and alert.

In exchange for the plea, federal prosecutors will agree to a prison sentence that probably will be in the range of 18 to 24 months, plus $63,000 in restitution to pay for the damage Brux did to the switches.

The court itself is not a party to the agreement and has the right to not accept the recommended prison term in the pending presentence report, Skavdahl said. Skavdahl set his sentencing for April 10.

Brux, who was 22 when arrested, was charged with “violence against railroad carriers and mass transportation systems on land, on water, or through the air.”  Conviction carries up to 20 years behind bars and a $250,000 fine.

He remains free on bond, in the custody of his mother who monitors his mental health evaluation and care. His public defender David Weiss previously told the court Brux has had a history of bipolar disorder and attention deficit hyperactivity disorder, but no history of encounters with law enforcement.

According to court documents filed with the case, Brux received a call early Thursday, Oct. 9, from a supervisor at Rail Link where he worked as a utility coal operator for three years at the North Antelope Rochelle Mine.

The call angered him. He then uncoupled two Burlington Northern Santa Fe locomotives at the North Rochelle Antelope Mine in Campbell County. Brux went “around the loop’” and “‘pretty much squashed the f— outta their scales’” and blew the locomotive’s horn to alert people, according to court documents.

He entered the main line -- one of the busiest lines of track in the country -- and drove them south for 13 miles into Converse County.

Meanwhile, a BNSF dispatcher stopped all traffic on the lines to avoid a collision.

A switch that sent Brux into the North Antelope mine. He came upon an idle Union Pacific train, hoped no one was on it or under it, and hit it while traveling about 10 mph. He backed up, went forward and hit it again, and was about to do it a third time when a Rail Link employee was able get on the locomotive and hit the fuel cut-off switch.

Brux fled on foot, and a Campbell County Sheriff’s Office deputy found him walking along a creek bed near the crash site.