A 43-year-old woman has been arrested on suspicion of murder following the discovery of two young children's bodies in a car in Heathfield.
Sussex Police said the woman is believed to be from Surrey, but with local connections. She was arrested after visiting Heathfield police station on Wednesday morning to report an incident.
Officers discovered the bodies of a boy and a girl, both aged under 5, after forcing entry into a car in Mill Close.