Human rights campaigners are organising a last-ditch attempt to stop the former Chilean dictator General Augusto Pinochet being returned home.

Meanwhile relatives of victims of the Pinochet regime have appealed to Scotland Yard to charge the former dictator with torture, and Spain is requesting that he undergo further medical tests.

Home Secretary Jack Straw said last Tuesday he was "minded" to let General Pinochet return to Chile in seven days' time.

Mr Straw's move came after a team of independent medical experts said the 84-year-old general was unfit to be extradited to Spain.

With the deadline for submissions to the Home Office on the subject due to expire at 1700GMT on Tuesday, several groups are planning to oppose the decision.

Spain's Judge Baltasar Garzon, who secured the former dictator's arrest in London in October 1998, has requested that the general undergo further medical tests.

The Spanish foreign ministry said it had forwarded a petition from the judge who wants the tests to be carried out by doctors of his choice, and also wishes to question the general.

Amnesty International also said they might seek an immediate judicial review of the way the medical examination on General Pinochet was carried out.

They have criticised the tests for being carried out in secret, without either medical experts or observers appointed by the other parties involved, and without any details from the medical report being released.

An Amnesty spokesman said: "Even someone accused of mass torture has the right to a fair legal process.

'Mockery of justice'

"But the procedure followed by Jack Straw over Pinochet's medical tests has been totally irregular and flouts natural justice.

"This process risks becoming a mockery of justice. The story in The Observer adds to growing concerns already expressed in Spain and elsewhere about the conduct and conclusions of Pinochet's medical examination."

A delegation of relatives of the "disappeared" met Assistant Commissioner David Veness on Monday to lobby for an investigation into General Pinochet under UK law.

The delegation, led by Labour MP Jeremy Corbyn, included Mercedes Rojas, whose husband Oscar vanished during General Pinochet's 17-year rule in Chile.

Mr Corbyn said Mr Veness had confirmed Scotland Yard had a file on the general and was considering whether to take any action.

"As part of the investigation into Pinochet these women have been forced to reveal extremely unpleasant and hurtful details about their experience, yet Jack Straw refuses to reveal the medical evidence on which he plans to send the dictator home."

Magistrates last year gave the go-ahead for the extradition of the former dictator to Spain on 35 torture charges relating to incidents during his 17-year regime in Chile.

But Mr Straw announced last week that the four-strong team of medical experts, appointed by himself, had concluded "unequivocally and unanimously" the general was unfit to stand trial.