An Army soldier was arrested for allegedly passing on bomb-making instructions to fellow "radicals" and sought to blow up cell towers and news stations, authorities announced Monday.

Pfc. Jarrett William Smith, 24, stationed out of Fort Riley in Kansas, was arrested Saturday and charged with one count of distributing information related to explosives and weapons of mass destruction, U.S. Attorney Stephen McAllister said.

In a chat Friday on the cloud-based instant messaging service Telegram, an undercover agent said he wanted to target a "liberal Texas mayor" for bombing and asked Smith if he had any other suggestions, according to an affidavit by FBI Special Agent Brandon LaMar.

"Outside of Beto?" Smith allegedly responded, in an apparent reference to Democratic presidential candidate and El Paso native Beto O'Rourke. "I don't know enough people that would be relevant enough to cause a change if they died."

Smith is a native of Conway, South Carolina, and had previous stints at Fort Benning in Georgia and Fort Bliss in Texas, according to a U.S. Army spokesman.

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The suspect made an initial court appearance on Monday and was ordered to remain in jail until at least his next date before a judge. That will be Thursday afternoon in federal court in Topeka.

A defense lawyer for Smith could not be immediately reached for comment.

“We’re grateful to the FBI for their diligence in handling this case and for their work to keep our country safe in the face of domestic terror threats," O’Rourke’s campaign press secretary Aleigha Cavalier said. "We take any threat like this very seriously, and our team is in direct contact with the FBI regarding this case.”

This past August, Smith told an FBI source that he also wanted to conduct "an attack within the United States" and that he was "looking for more 'radicals' like himself," according to LaMar.

"Smith talked with the confidential source about killing members of the far left group, Antifa, as well as destroying nearby cell towers or local news station," the affidavit said.

And on Aug. 21, Smith specifically told an undercover agent that he wanted to build a "large vehicle bomb" to attack a major news outlet, according to the FBI.

Smith said ordinary household chemicals could be used for bomb-making but said it's important to buy the materials separately so "the randomness will aid you in the case of searches and the materials themselves usually aren't considered suspicious," LaMar wrote.

Smith, who enlisted in the Army in June 2017, could face up to 20 years in federal prison and a fine up to $250,000 if convicted.

Before talking about his alleged desire to target news stations, Antifa and O'Rourke, Smith's fascination was with a far-right Ukrainian paramilitary group, according to LaMar.

During his 2018 flirtation with the Ukrainian militia, Smith passed on instructions on how to make improvised explosive devices that could be detonated with a cellphone, according to the FBI.

"Oh yeah, I got knowledge of IEDs for days," Smith allegedly wrote in a Facebook chat on Dec. 18, 2018. "We can make cell phone IEDs in the style of the Afghans. I can teach you that."

LaMar said he took Smith's IED-making instructions to an FBI bomb technician who confirmed that the suspect's directions were accurate.