Simon Mann was finally reunited yesterday with the family he has not seen for five years, and the son he has never met, but his hopes for a private and peaceful homecoming may be shortlived.

Scotland Yard counter-terrorism detectives are preparing to question the Old Etonian mercenary, who was freed after serving 15 months of a 34-year sentence in the oil-rich West African state of Equatorial Guinea.

His African adventure might have ended as soon as he stepped on to the tarmac at Luton airport yesterday afternoon, but his arrival in England begins a new chapter in the real-life thriller that is likely to focus on the moneymen behind the mercenaries.

Before leaving Africa yesterday, Mann, 57, said: “I am very anxious that [Ely] Calil, [Sir Mark] Thatcher and one or two of the others should face justice.”

The so-called “Wonga coup” collapsed when Mann and a team of up to 70 mercenaries were held on an airport runway in Harare, Zimbabwe, in March 2004. During his trial, Mann claimed that Sir Mark, the disgraced son of the former Prime Minister, was “part of the management team” in the plot to install Severo Moto, the Equatorial Guinea opposition leader.

He also named several other prominent figures who allegedly helped to organise and finance the plot in London, including Mr Calil, a Lebanese-Nigerian tycoon and friend of Lord Mandelson, whom Mann said masterminded the plan. Mr Calil has always denied the claims.

If he decides to repeat the allegations, his former associates could be questioned by police about the alleged coup attempt. Mann said that he had made statements to British detectives while he was in jail and added: “I am very happy to restate those things in court in the UK as a witness for the prosecution.”

No Metropolitan Police officers were waiting for Mann yesterday, although police sources confirmed that they intended to speak to him “very soon”. A spokesman said: “We can confirm we are investigating whether any offences may have been disclosed in this country. We are aware of developments but are not prepared to discuss them further.”

Officers from Counter Terrorism Command visited Equatorial Guinea three times last year between July 28 and October 20 and spoke to Mann on “a couple of occasions”.

Arriving in a private jet, Mann, 57, said it was the “most wonderful homecoming I could ever have imagined”. He is likely to receive lucrative offers from publishers and newspapers seeking answers to questions that remain over the bungled 2004 plot to topple Equatorial Guinea’s government.

The former SAS soldier touched down at Luton at 1.32pm, having been released from his Equatorial Guinea prison cell 33 years earlier than expected. He said that he was looking forward to meeting his youngest son, whom he had never met. “There hasn’t been a moment during the last 5½ years when I have not dreamt of one day being back in Britain with my family,” he said in the statement, read out by Ian Monk, a family spokeman.

“I’m especially looking forward to meeting my son Arthur, who was born a few months after I left the country and whom consequently I have never seen. I am hugely grateful to President Mbasogo for releasing me. It’s the best early Christmas present my family and I could ever have imagined.”

His family spokesman said he would be spending time with his wife and family “somewhere quiet”, believed to be his 20-acre estate near Beaulieu in the New Forest.

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