The Secret Service arrested a Wisconsin man Thursday after he allegedly told a security guard he planned to kill President Obama, a federal official confirmed to Fox News.

55-year-old Brian Dutcher of Tomah allegedly made the threat the same day Obama was in La Crosse touting a proposal to make more workers eligible for overtime pay.

Dutcher allegedly told a security guard at a La Crosse library, “the usurper is here and if I get a chance I’ll take him out and I’ll take the shot,” referring to Obama, MyFox8.com reported. According to the affidavit, Dutcher told a La Crosse police detective his threat was serious.

U.S. Attorney John Vaudreuil told the Wisconsin State Journal Dutcher was being held in the mental health facility.

Fox News' Lesa Jansen and The Associated Press contributed to this report.