Two men burst into a Grass Valley pharmacy Tuesday afternoon during an altercation that allegedly began over a domestic violence incident, knocking over displays, throwing items grabbed off the shelves and sending employees and customers running for safety. Officers from Grass Valley and Nevada City Police departments, Nevada County Sheriff’s deputies and California Highway Patrol officers all converged on the Spring Hill Pharmacy in the 100 block of Catherine Lane, after a 911 caller reported a fight possibly involving a gun and a knife at about 2 p.m. Two Grass Valley Police officers made entry into the building and quickly …