Updated

Federal authorities said Monday that they believe the man known as the “AK-47 bandit” has been arrested.

FBI agents were tipped off when Richard Gathercole called his mother from a Nebraska jail following is arrest in the shooting of a Kansas trooper last week, according to court records. The trooper was not injured in the shooting.

The "AK-47 bandit" has been linked to several bank robberies and police shootings across the U.S.

According to a transcript of the call, Gathercole told his mother to "get all the guns out" of the house. The woman agrees, then says, "Um, this is recorded. You know that."

FBI agents, along with officers from California, Idaho and Montana, searched Gathercole’s home in Roundup, Mont. and discovered “numerous” IEDs, officials said.

FBI officials in Los Angeles confirmed that the search was connected to a bank robbery investigation.

"Multiple departments are investigating whether evidence found during the search in Montana may be linked to a series of bank robberies currently under investigation in California and other states," an FBI Los Angeles spokeswoman said.

FBI officials have been searching for the “AK-47 Bandit” since 2012. The suspect is wanted for several heists across California, Iowa Washington state and Nebraska. The suspect typically wore a balaclava mask and carried an AK-47 rifle with a drum magazine during the robberies, according to FBI officials.

The robber shot and wounded an officer in Chino, Calif. while trying to escape one robbery, the FBI said.

The FBI’s search applications details robberies allegedly carried out by Gathercole: one where he allegedly stole more than $90,000 from a bank in Nebraska City, Neb. in 2014, and another where he allegedly stole $126,000 in Mason City, Iowa and used an explosive device during the heist.

The search warrant application did not describe other “AK-47 Bandit” robberies.

Gathercole is being held on charges of theft and possession of stolen firearms. He was arrested last Tuesday at a gas station in Lexington, Nebraska. He had stolen a truck and guns as he was trying to get away from the Kansas trooper, according to officials.

Federal charges have not been filed against Gatherole. According to KRTV, the FBI was offering $100,000 for the arrest of the robber.

The Associated Press contributed to this report.