The Post Office is contacting hundreds of people who may have been wrongfully prosecuted following the subpostmaster miscarriage of justice scandal.

Dozens of subpostmasters were prosecuted for theft, fraud and false accounting because of the Post Office’s defective Horizon accounting system, which had “bugs, defects and errors” from the outset.

Last month, 39 former subpostmasters who were convicted and even jailed based on Horizon data had their convictions overturned by the Court of Appeal.

The Post Office sincerely apologises for serious historical failures. We continue to take determined action for people affected

The Post Office said it is contacting around 540 people with potentially relevant convictions and additional information is being sought in another 100 cases.

A spokesman said: “The Post Office sincerely apologises for serious historical failures. We continue to take determined action for people affected.

“Post Office has made strenuous efforts to identify individuals who were historically convicted and an extensive post-conviction disclosure exercise is taking place to identify and disclose all material which might affect the safety of those convictions.”