5.15pm update

Mark Thatcher 'was planning Texas move'

Sir Mark Thatcher was planning a move from South Africa to Texas when he was arrested over alleged involvement in a coup plot, a South African prosecutor said today.

Margaret Thatcher's son is under house arrest and facing the possibility of 15 years in prison after being accused over an alleged plot to overthrow the government of oil-rich Equatorial Guinea.

The 51-year-old, who denies the charge, was arrested at his Cape Town home early yesterday, and appeared in court in the city later that day.

Makhosini Nkosi, a spokesman for the National Prosecuting Authority, today said: "It does appear that he was planning to leave the country.

"The house was on the market, he had disposed of some of the cars, and there were suitcases around the house which indicated they were planning to leave. He did confirm he was planning to relocate to Texas."

Sir Mark has been charged with violating South Africa's anti-mercenary law in connection with the alleged coup attempt. Prosecutors allege that he helped finance a purported attempt to overthrow Equatorial Guinea's controversial president, Teodoro Obiang.

Seventy people are on trial in Zimababwe in connection with the alleged plot. The majority of them were arrested at an airport in Harare in March, where they had been aboard a plane allegedly bound for Equatorial Guinea. Another 19 are on trial in Malabo, the capital of Equatorial Guinea.

Prosecutors claim the men on the plane were mercenaries led by Briton Simon Mann, 51. Mr Mann is the founder of Executive Outcomes, a mercenary company, and a neighbour of Sir Mark in South Africa. He was arrested on the plane in Harare and is currently in a prison in Zimbabwe while his trial continues.

The Equatorial Guinea government has accused the millionaire oil trader, Ely Calil, of having helped to organise a coup from his west London home, and has issued a warrant for the arrest of David Hart, a former adviser to Malcolm Rifkind and Michael Portillo.

The exact role of the British authorities in the affair was today unclear, with the Metropolitan police refusing to comment on what representations it had received from Equatorial Guinea and South Africa, or what extradition procedures it was involved in.

A spokesman for New Scotland Yard would only confirm that it was in discussions with the Home Office about how to proceed, having received a letter from a firm of solicitors. The spokesman would not comment on who the solicitors were acting for.

Asked about the discussions with the police, a Home Office spokeswoman told Guardian Unlimited that "the UK would always stand ready to assist other countries with matters of judicial cooperation or mutual legal assistance".

Sir Mark's lawyer, Peter Hodes, yesterday said that his client had been arrested on suspicion of providing finance for a helicopter linked to the alleged plot. "He will plead not guilty," Mr Hodes said.

In a statement released by his spokesman, Lord Bell, yesterday, Sir Mark said: "I am innocent of all charges made against me. I have been and am co-operating fully with the authorities in order to resolve the matter.

"I have no involvement in an alleged coup in Equatorial Guinea, and I reject all suggestions to the contrary."

Lord Bell said Sir Mark was due to return to court in mid-November. A magistrates court in Cape Town yesterday set his bail at two million rand (£175,000). He was placed under house arrest, and has until September 8 to post his bail.

Sir Mark, who inherited the baronetcy of his late father, Sir Denis, last year, could face a 15-year prison sentence if convicted, according to a police source.

The alleged plotters were said to be hoping to exploit Equatorial Guinea's huge oil reserves by installing their own leader, Severo Moto, who is currently in exile in Spain.

Others implicated in the alleged plot include South African arms dealer Nick du Toit, who faces the death penalty if convicted. His co-defendants face prison sentences of up to 86 years if the case is found proved against them.

The 19 people on trial in Equatorial Guinea are charged with attempting to assassinate a head of state, illegal possession of arms and explosives, terrorism, treason and endangering the public. Verdicts in their cases are expected on Saturday.

Equatorial Guinea pumps 350,000 barrels of oil a day, and has become Africa's third-largest oil producer since offshore development began in the mid-90s.

Baroness Thatcher has declined to comment on the situation.

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