The Portuguese detective leading the investigation into the disappearance of Madeleine McCann was sacked yesterday after he accused British police of helping her parents to cover up their role in their daughter’s death.

Chief Inspector Gonçalo Amaral, who has been the driving force behind briefings that the couple were responsible for the disappearance of their daughter, was dismissed from his position as director of the Polícia Judicaria in Portimao and demoted to the rank of inspector.

The detective was summoned to a meeting with Alipio Ribeiro, the national director of the Polícia Judicaria, in Faro, after telling a Portuguese newspaper that British police were helping to protect Kate and Gerry McCann.

Mr Ribeiro had earlier criticised officers who spoke to the press. “The police should be discreet and keep quiet, but there is always someone who talks,” he said in an interview in August. “Sometimes it is someone who knows nothing and just wants to be a protagonist.”

Mr Amaral’s extraordinary attack came after two weeks of new claims that have cast doubt on the Portuguese police case that Mrs McCann killed Madeleine accidentally at their holiday apartment on May 3.

He told Dario de Notícias: “British police have only worked on what the McCann couple want them to work on. They have only investigated tips and information developed and worked on for the McCanns, forgetting that the couple are suspects in the death of their daughter, Madeleine.”

The comments were seen as highly embarrassing for the Portuguese authorities and led Alberto Costa, the Justice Minister, to insist that there was “fruitful co-operation” between the police forces of both nations.

Mr Costa, who was asked about the row as he attended a public event near Lisbon, said he wanted officers “to concentrate on the job and not on the comments” made by Mr Amaral.

A police spokeswoman said last night: “We can confirm that Mr Amaral is no longer working for the Judicial Police in Portimao. The decision was taken by the national leadership on Tuesday. We cannot make any comment on the reasons for his dismissal, but we can confirm that he did not resign. He was removed from the post.”

Mr Amaral’s dismissal was perceived in Portugal as a hugely significant development in the case against Mr and Mrs McCann. The 47-year-old detective has made little secret of his belief that the couple are behind the death of Madeleine.

Despite Portugal’s strict judicial secrecy laws there has been a constant trickle of information from inside the police investigation. It is thought that Mr Amaral believed he was talking off the record when he made the comments that led to his downfall.

Mr Amaral was particularly critical of reports that British police were taking seriously an e-mail sent to the official website of the Prince of Wales last week. The tip-off claimed that Madeleine had been abducted by a maid in revenge for being sacked from the Ocean Club complex, where the McCanns were staying.

He told the Dario de Notícias that the lead had “no credibility” for the Portuguese police. “This story about abduction for revenge is another lead being worked on for the McCanns. The Ocean Club is in Praia da Luz, not London, which means everything said by employees, current or former, has already been investigated.”

An unnamed senior police source said: “After the war with the British media, we now have another with the English police.”

Leicestershire Constabulary, which is leading the British side of the investigation, refused to respond to the criticism, saying only that it continued to support the Portuguese police.

Friends of the McCanns said that Mr Amaral’s comments were “completely wrong”. One said: “Leicestershire police are not investigating things purely because the McCanns ask them. There’s no way that would be entertained.”

The timing of Mr Amaral’s outburst and sacking will concern the Portuguese prosecutors, who are preparing to ask for British detectives to reinterview the McCanns. They want the couple to be asked 40 questions that they refused to answer before being made official suspects last month.

There had been criticism of Mr Amaral’s appointment to the case because he faces a criminal hearing over allegations that he covered up the torture of a mother accused of murdering her daughter.