Fifty-nine-year-old Christopher Bruce was arrested Thursday, according to an arrest affidavit.

KSFY TV is reporting that Bruce allegedly sent a series of threatening messages to Mayor Paul TenHaken beginning in November of 2018.

Following the first message, a Sioux Falls police detective contacted Bruce, and advised him that his message could be construed as threatening. Bruce said he would no longer send messages to TenHaken directly.

A few days later, Bruce then allegedly sent an email to the Sioux Falls City Council, where he mentioned being contacted by police.

According to the affidavit, the email included the statement: "Evidently, the mayor got a little wake up call, because it hit home that maybe his family might find out that their son may be responsible for the deaths of the citizens of the city he's in charge of, someday."

Bruce is no stranger to the city council. He has frequently spoke at council meetings, railing against what he said were the dangers of wireless 5G technology.

In March, Bruce then allegedly sent another email directly to TenHaken, saying "I say you can fight city hall, you just need a bigger gun, better bullets, and harder armor." TenHaken notified police, and officers again contacted Bruce about the message.

On May 17, Bruce sent another message to city council members, stating "This is your notice that the next public input session is about to be the most explosive to date," according to the affidavit.

Detectives say a couple weeks later, Bruce made an online post saying he will make a "special effort" to reach out to TenHaken's family in Minnesota. Sioux Falls police contacted the Worthington, Minn. police department about the threat.

The day before he was arrested, Bruce allegedly sent another email directly to TenHaken, reiterating his previous threats.

Bruce was arrested Thursday on a stalking charge, which is a class 1 misdemeanor, punishable by up to one year in prison.

City spokesman T.J. Nelson issued a statement to KSFY News regarding the arrest, stating: "The City takes threats against the safety of the Mayor, City Council members and their family members extremely serious."

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