A collection of letters written by a famous gangster Reggie Krai will be sold at auction during imprisonment, it is reported BBC.

Cray wrote the letters while he was serving a life sentence for the 1967 murder of hitman Jack McVitie.

Together with his twin brother, Ronnie Kray built a criminal empire in London in the 1950s and 1960s.

The letters will be sold during a three-day auction starting on February 10.

In 1968, Reggie was charged with murder and convicted the following year.

He spent most of his days behind bars until he was released on compassionate grounds in 2000 to spend his final weeks with his second wife, Roberta Jones.

He died in a Norwich hotel of bladder cancer on 1 October 2000, aged 66.

Mike Tyson allegedly wrote letters to Reggie Cry while in prison and said he was threatened with deportation from England in 2000, Sport Bible reports.