Sussex Police is investigating reports of a man approaching and following a 13-year-old girl in Lancing.
A police spokesman said the girl reported being approached by a middle-aged man shortly before 6pm on Monday (October 7) in Crabtree Lane, Lancing.
He was driving a black car, said the spokesman, and asked if she wanted a lift, but she declined.
Police said the girl later saw the same man in Cokeham Road, Sompting, where he appeared to be filming her.
Officers are making further enquiries, police added.