FOUR documents relating to the execution of North-East serial killer Mary Ann Cotton have been auctioned for five times their estimated price.

The documents went on sale at Tennants Auctioneers, in Leyburn, North Yorkshire, as part of its specialist book sale yesterday and were sold for £2,600.

A telegram from the Deputy Governor of Durham County Prison to the Coroner for Chester Ward, County Durham, dated March 22, 1873, is included in the lot giving instructions for an inquest following Cotton’s execution while the official Crown warrant along with five signed witness statements identifying Cotton’s body and the ‘Inquisition’ death certificate were also included.

Cotton was born Mary Ann Robson in 1832 near Hetton-le-Hole.

In 1873 she was convicted and hanged for the murder of her stepson Charles Edward Cotton, but it is believed she may have murdered up to 21 people, including 11 of her 13 children and three of her four husbands. Her chief weapon was arsenic.

Tennant’s book specialist, Jasper Jennings, said the documents had generated “fierce” bidding both in the sales room and online.

He said: “The final price was more than we have made on letters written in the hand of Mary Ann Cotton which meant it was a slightly surprising price. I can only put this down to media interest in the sale and the series that on in November.”