A man who had been arrested on suspicion of murder after a body was found in a Suffolk lake has been detained under the Mental Health Act.
A woman's body was found at Needham Market on Sunday and the man was arrested later at Wissett Lake, near Halesworth, 30 miles away.
The 58-year-old from Ipswich had been kept in custody in hospital but is now no longer under arrest, police said.
The woman has been identified but her next of kin have not been traced.
A cordon remains in place at Needham Market lakes.