LOS ANGELES—After a series of hit-and-runs in the Jefferson Park area of Los Angeles, authorities Jan. 20 were asking for the public’s help, hoping that rewards of up to $25,000 would aid in solving the crimes. On Jan. 5, 46-year-old Nallely Oregel was walking her dog on Fourth Avenue at 30th Street when a silver mid-size SUV traveling at a high rate of speed ran off the roadway onto the sidewalk and struck her and her dog. On Jan. 7, 25-year-old Giovanny Castro was riding a scooter south on Western Avenue at 29th Street when he was struck from behind by a gray compact vehicle traveling at a high rate of speed. And on Jan. 11, a man who was walking on a roadway in the Jefferson Park area was struck by a maroon Chevrolet Trailblazer. He suffered “massive head trauma” and remains on life support, police said. “In all …