A man wearing a gas mask while driving Monday morning created an alarming scene in downtown San Mateo after officers reportedly found an inactive grenade inside his vehicle. Just after 9 a.m. on East Fourth Avenue, police said, 29-year-old Gilberto Masias was stopped by officers who said they were alarmed by his apocalyptic-looking headgear. The gas mask might have been part of a Halloween costume, as police said Masias works at a local costume store. Read More