Updated

The Pinal County Sheriff's Office in Arizona is investigating a prank that prompted officials to interrupt grand jury proceedings.

Sheriff Paul Babeu says a Casa Grande man who was serving as the jury foreman found a threatening handwritten note on his truck last week when he took a lunch break. It suggested that whoever left the note had followed him home.

[pullquote]

Detectives were able to trace the note to a restaurant in Florence, where they learned that two men had asked a waitress to write it so they could play a prank on their co-worker and friend, the jury foreman. The waitress complied, but reportedly told the men it was a bad idea. One of the men who was not cited in the incident said they planned to reveal the prank to the co-worker the following day.

"The trauma inflicted on the foreman, the risk of wrongful arrest for the innocent writer of the note, the great expense of the all-out investigation by PCSO, and most importantly, the overall potential risk of tampering with the integrity of our judicial system requires my office's action," Lando Voyles, the Pinal County attorney, told The Arizona Republic.

Babeu says the case will be reviewed for possible criminal charges, including influencing a juror and disorderly conduct.

The Associated Press contributed to this report