This story is developing.

UPDATE:

The Tennessee man accused of planning to attack a Muslim community in New York is in custody after jurors convicted him today in Chattanooga's U.S. District Court.

Around lunchtime, jurors told U.S. District Judge Curtis Collier they had reached a verdict in the case of Robert Doggart, a 65-year-old former engineer at the Tennessee Valley Authority who faced four federal charges.

Former Tennessee Valley Authority engineer Robert Doggart is escorted from the Joel W. Solomon Federal Building in Chattanooga after his four count conviction of planning an attack on a Muslim community.

Their verdict was much anticipated after jurors announced Wednesday they could not reach a unanimous decision. Instead of granting a mistrial, Collier told them to return today, and jurors spent another three hours deliberating.

After the verdict, Doggart's defense attorneys asked Collier to let him stay on house arrest before his May 31 sentencing hearing, citing medical problems. Since his arrest in April 2015, Doggart has spent most of the time out on bond, records show.

Collier, however, said Doggart appeared obsessed with the community of Islamberg and would not grant the request.

Since last week, Collier had listened to many wiretapped phone calls that prosecutors played of the Sequatchie County, Tenn., man talking to would-be supporters. Doggart was arrested April 9, 2015, before he could make a trip to Islamberg, prosecutors said.

After Collier made his decision, U.S. Marshals escorted Doggart into a side room. They asked him to leave his possessions, and his family, behind.

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After two full days of deliberation, jurors announced they could not reach a "unanimous decision" in the case of Robert Doggart, a former Tennessee Valley Authority engineer who is accused of planning an attack on a Muslim community.

They passed a note to U.S. District Court Judge Curtis Collier around 4:30 p.m. Wednesday, saying they needed instructions on how to proceed with Doggart's one count of solicitation to commit a civil rights violation, one count to commit arson of a building, and two counts of threat in interstate commerce.

Instead of granting the defense's request for a mistrial, Collier told jurors to go home, get their minds off the case, and return today at 9 a.m. to try again. It's unclear whether jurors are hung on all four of Doggart's charges or just a few.

It was not the only time the jury had questions Wednesday. They stopped two hours into morning deliberations to ask for clarification on threats in interstate commerce charges, of which Doggart faces two.

Typically, the federal government regulates interstate commerce, which often refers to the movement of goods or people across state lines. In this case, prosecutors said Doggart made two threats against Islamberg near Hancock, N.Y., in phone conversations with supporters in South Carolina and Texas. The threats occurred March 22, 2015, and April 9, 2015, prosecutors said, and the Federal Bureau of Investigation was monitoring both communications after a local judge had authorized a wiretap a few weeks before. That surveillance also included a helicopter that followed Doggart on a trip to South Carolina, testimony revealed.

A telephone counts as an instrument of interstate commerce, prosecutor Perry Piper said Wednesday during the short debate that followed the jury's question, and the government provided ample proof of Doggart making threats over one.

"You'd like me to add the sentence, 'The government need only prove the use of instrumentality or that the transmission occurred in interstate commerce. However, the government need not prove both?'" Judge Collier asked him.

Piper said yes, arguing that Collier could "sweep away" the confusion some jurors were having with a clarification note.

Since last week, prosecutors have played many phone calls to jurors in which Doggart talked about burning down Islamberg's mosque with explosives and shooting anyone who opposed his team with assault rifles.

Defense attorneys, though, countered that Doggart exaggerated a number of facts, never had a consistent plan in place, was goaded by a confidential informant into carrying out the attack, and only wanted to conduct peaceful recon on Islamberg. He was convinced Islamberg's residents wanted to carry out a terror attack on New York City, in part because of Fox News broadcasts, defense attorney Jonathan Turner told jurors in his closing arguments Monday afternoon.

The defense also claimed there were issues with the government's interstate commerce charges. During a cross-examination with an Islamberg resident who runs a bookstore from the community mosque, Turner implied the business wasn't affected by Doggart. Zavia Books made its first sale in the summer of 2015, Turner said, about three months after Doggart's arrest.

Ultimately, Collier agreed with prosecutors, adding a sentence to clarify the issue of interstate commerce for jurors. Essentially, the government only needed to prove that Doggart used a telephone to make the threats — or, that his threats happened across state lines.

Federal prosecutors can only refile charges in the Robert Doggart case if his trial ends with a hung jury.

But attorney Tahirah Amtaul-Wadud, who is representing Islamberg in a separate civil lawsuit against Doggart, said the community respects the work of the jury.

"The feeling of the community is one of gratitude to the jury and deep respect for their work, along with a deep appreciation for the fact that what they're being asked to do takes a great deal of courage," she said. "We want the entire region — that whole Tennessee area — to know those points are not wasted on us."

Contact staff writer Zack Peterson at zpeterson@timesfreepress.com or 423-757-6347. Follow him on Twitter @zackpeterson918.

Clarification: Federal prosecutors can only refile charges in the Robert Doggart case if his trial ends with a hung jury. If the jury acquits Doggart, prosecutors can't retry him on the same charges, as the Times Free Press incorrectly stated. That would be double jeopardy.