Robbery suspect implicated in letter A suspect in several robberies in La Jolla and a burglary in Pacific Beach has been implicated in the crimes after an anonymous letter naming him responsible turned up at the Alpine sheriff’s station. At the time, David Allen Grub, 43, was living in Alpine, but no one seems to know who left the letter on Feb. 21. He was arrested Feb. 28 and a declaration by a sheriff’s detective said it was either written by Grub or someone familiar with the details of the crimes. The letter contained details about the crimes which had not been made public. Grub has pleaded not guilty. A preliminary hearing has been set for May 8. The first burglary occurred on May 24, 2012 on Loring Street in Pacific Beach at 10 a.m., when the resident returned home and saw a suspect carrying a drawer from his dresser. The suspect fled in a black car, and the victim discovered a large amount of jewelry was stolen. Grub remains in custody on $300,000 bail.