KARE 11 reports that authorities have a person of interest in a series of bomb threats that closed five north metro post offices Friday morning. Post offices in Robbinsdale, Elk River, Anoka, Coon Rapids and Brooklyn Center were evacuated and searched after the threats were received in the mail. KSTP reported that Capt. Scott Nolan of the Anoka Police Dept. saidsurrounding neighborhoods in Anoka were not affected.