Hackers behind the leak of emails in which David Beckham complains about being snubbed for a knighthood reportedly demanded one million euro from the sports agency representing him.
Police in Portugal, where Doyen Sports has an office, have been investigating the attempted blackmail for a year.
Beckham was not the explicit target of the hack, a source told the Daily Mirror, but was “caught in the crossfire”.
A source said: “They approached by email and attempted to meet via another third party.
“They said we have all this information and you have to pay up. It was blackmail, pure and simple.”
The leaked emails included one in which Beckham lambasts the honours committee which decides on recipients as “a bunch of c***s” and brands the honours system as “a f****** joke”.
A representative of the former England captain dismissed the contents of the messages as “outdated material taken out of context from hacked and doctored private emails from a third-party server”.
He said the material “gives a deliberately inaccurate picture”.
The Daily Mail reported Beckham was on the verge of receiving a knighthood in the 2014 New Year’s Honours list but HM Revenue and Customs placed a red flag on his nomination due to his involvement in an alleged tax avoidance scheme.
In response to his PR chief’s email notifying him of the red flag, the newspaper said Beckham wrote: “The flag has no truth behind it as we didn’t (do) nothing wrong everything is and was above board...C***s.”
Also in the leaked emails, Beckham is said to have questioned the OBE given to singer Katherine Jenkins, referring to a past admission she had taken drugs.
In response, a representative defended Jenkins, issuing a “fact sheet” listing her charity work and success in the music industry.
He said: “With regards to the taking of coke which Katherine has courageously publicly admitted with great honesty - this was when she was in her early 20s still a student - over a decade before she was awarded her OBE and started her recording career.”
Other emails reportedly saw Beckham react negatively to a suggested donation to Unicef, of which he is a goodwill ambassador.
The charity said: “Unicef has become aware of media reports relating to 7: the David Beckham Fund for Unicef.
“Some reports relate to alleged private correspondence between our ambassador and other parties, which we have not seen and cannot comment upon.”
It added: “We are extremely proud of the 7 Fund and all it has achieved for children.”
Beckham was given an OBE for services to football in 2003 on the recommendation of then prime minister Tony Blair.
His wife Victoria got the same honour for services to the fashion industry in the most recent New Year Honours list.
On Sunday, Beckham’s eldest son Brooklyn posted a picture of the former footballer on Instagram, sitting at a dinner table cuddling his daughter Harper.