A woman was stabbed in Brockton and flown to a Boston hospital Sunday evening, according to Brockton police Sergeant Mark Celia. The woman was stabbed in the vicinity of Loucraft Avenue at about 7:30 p.m., he said. Celia said that no arrests had been made and that the stabbing remained under investigation. He would not confirm a report that a 10-year-old had called police after witnessing the stabbing at Leslie B. Parmenter Park. The Enterprise newspaper in Brockton, citing police sources, reported on its website Sunday night that two children, who were not injured, were taken by ambulance to a local hospital for evaluation. The newspaper reported that officers found a weapon at the scene and that witnesses told police they saw four teenagers run after the stabbing.