One of the Hatton Garden raiders has admitted burgling a high-end London jewellers five years earlier.
Daniel Jones has admitted being involved in an attempt to break into a safe in Mayfair, which contained millions of pounds worth of jewellery, on the August bank holiday weekend in 2010.
The 62-year-old is currently serving a seven year prison sentence after pleading guilty to conspiracy to commit burglary, following his role in £14 million Hatton Garden jewellery raid in 2015, the largest burglary in English legal history.
Jones, from Enfield, pleaded guilty at Southwark Crown Court on Friday, ahead of a trial of two other men which is due to take place later in February.
Terry Perkins, 68, has denied attempting to access a safe at Chatila jewellers in Old Bond Street containing jewellery worth £40 million and making off with more than £1 million of goods between Saturday, August 27, and Tuesday, August 31, of that year.
Charles Matthews, 54, from Virginia Water, Surrey, denies one count of handling stolen goods.
He and Perkins, also of Enfield, are due to stand trial on February 27.