A 36-year-old Phoenix man was arrested Thursday after officials said he made several threats to kill Sheriff Joe Arpaio, according to the Maricopa County Sheriff's Office.

A sheriff's spokesman said Raul Rentiera Rivera called 911 twice on Friday and told the dispatcher he'd kill Arpaio "because he's a racist."

Then on Sunday, when he was taken into custody by Phoenix police in an unrelated DUI incident, he repeated the threat against Arpaio, according to Officer Christopher Hegstrom, a spokesman for the Sheriff's Office.

Rivera has been booked on two counts of threatening and intimidating the sheriff, a Class 6 misdemeanor, as well as a count each of aggravated DUI and resisting arrest.