Police believe a Valley View grandmother was murdered after she was followed home by two men, with her daughter-in-law tied up during the terrifying attack. Neighbours have described hearing 'screaming' after an Adelaide grandmother was allegedly murdered in her home at Valley View last night. Police believe the 57-year-old was followed home from her work in Unley by two Caucasian men driving a white ute. The woman’s daughter-in-law was found bound and gagged, and managed to crawl to a nearby driveway. "A murder, a very deliberate, calculated and vicious attack," Det. Insp. Des Bray told 9NEWS. Neighbours Annie Noel and Laura-Lee Shanahan found the woman's 27-year-old daughter-in-law in a driveway with her ankles and hands tied and stayed with her until police arrived. "It was disgusting, it's awful. I've never seen someone so scared before," Ms Shanahan told 9NEWS. "We just kept her still and told her she was safe until the police got there."