The Middlesex District Attorney has dropped charges against Somerville resident Irina Kristy, who was accused of running a methamphetamine lab with her son out of their home on Oxford Street, according to Cara O'Brien, a spokesperson for the district attorney.
Kristy, 74, is a college professor who has worked as a lecturer in mathematics at Boston University and Suffolk University.
DEA agents and police raided her home, only a few blocks from Somerville City Hall, on Nov. 7, 2011, causing a stir in the community as agents in hazmat suits searched the residence, a state police bomb squad denoted chemicals allegedly found in the home and news helicopters hovered over the neighborhood.
O'Brien said that after a subsequent investigation by the Somerville Police Department and the district attorney's office, charges against Kristy have been dropped.
However, the charges against her son, Grigory Genkin, 30, remain, O'Brien said.
Genkin is accused of manufacturing and distributing methamphetamine, committing a drug violation near a school zone and conspiracy to violate drug law. He has pleaded not guilty.
Genkin is next scheduled to appear in Somerville District Court on Feb. 29 for a probably cause hearing, O'Brien said.