LOS ANGELES, May 24 (UPI) -- Civil rights activists are calling for an independent investigation into the shooting death of a homeless black woman by Los Angeles police. Police say the woman pushed her shopping cart into the officers and tried to stab one of the officers with a large screwdriver after they stopped to question her last week about a number of shopping cart thefts in the area. Police say 27-year-old Officer Edward Larrigan had to move suddenly to avoid being stabbed and fired one shot as the woman continued to try to attack him. She was shot in the upper torso and died soon afterward at the hospital. The Los Angeles County Coroner's Office identified the woman as 54- year-old Margaret Laverne Mitchell, whose last known address was in Long Beach. The director of Project Islamic Hope, Njee Ali, wants the Justice Department to look into the case to see if excessive force guidelines were violated, and is calling for a protest march Thursday outside the LAPD's headquarters.  