A 27-year-old Gardner woman was killed and her 9-year-old daughter injured when the car they were traveling in collided head-on with a pickup truck in Westminster Wednesday, officials said. The crash occurred just after 4 p.m. at Route 140 and Betty Spring Road, the Worcester district attorney’s office said. The driver of the car, Elisabeth M. Estrada-Turner, was later pronounced dead at Heywood Hospital in Gardner, the statement said. Her daughter was taken to a Worcester hospital, and the driver of the pickup and his son were taken to Heywood. A spokesman for the district attorney had no information on the condition of survivors Wednesday night.