The United States banned all imports of Mexican avocados after a safety worker was threatened by a suspected drug-cartel goon in what has become the latest in a growing turf war battle in the state of Michoacan. The ban will last “until further notice” and threatens the supply of avocados to the U.S. The decision to stop the imports was made after the safety inspector received a daunting threat via SMS on Saturday, the day before Mexican avocado growers launched a pricey Super Bowl ad.