Police are trying to trace the owner of a handwritten letter from the wife of Winston Churchill, which was recovered during a drugs raid.
Officers executing a warrant last month at a house in Mexborough, South Yorkshire, found the letter, and three cheques mounted on a card, inside a plastic sleeve with a quantity of heroin.
A 55-year-old woman was arrested on suspicion of theft and possessing class A drugs at the property. The woman's 32-year-old son and her sister, 41, were also arrested on suspicion of theft. They have been bailed until October while police make further inquiries.
The letter, dated 1942, is addressed to a married woman in the South Yorkshire area. The letter, signed by Clementine Churchill, says: "This is to acknowledge with grateful thanks your contribution to Mrs Churchill's Red Cross Aid to Russia Fund."
The Aid to Russia fund, set up by the Red Cross in 1941 to pay for clothing and medical supplies to send to Britain's Russian allies, raised £8m. Mrs Churchill was the fund's president.
PC Steve Roberts of Doncaster police said: "The address on the letter is not in Doncaster but it is South Yorkshire. I am confident it is not a reproduction as it is handwritten on both sides. We urge anyone with any information about the letter or who believes it may belong to them to get in touch with us." Doncaster police can be contacted on 01302 385199.