The incident happened about 2 p.m. on Feb. 11 at Mercer Street and Sproule Avenue.
Maria Pena, 28, was crossing the street with her 3-year-old daughter and two children she was babysitting -- a 2-year-old boy and a 5-year-old girl -- when they were struck by a gray, four-door pickup truck, according to police.
The three children were treated for moderate to serious injuries. Pena was pronounced dead at the scene.
The suspect left the location, failing to stop to render aid or identify himself. The suspect was described as a Hispanic man with spiked hair.
Anyone with information about this incident or the whereabouts of the driver or car was asked to contact detectives at 877-LAPD-24-7. Anyone wishing to remain anonymous should call Crimestoppers at 800-222-TIPS.