One word "ludicrous" was repeated over and over again yesterday following suggestions by Portuguese police that Kate McCann may have killed her missing daughter Madeleine.

From Gerry McCann's family in Glasgow, his wife's in Liverpool, their own home in Leicestershire and from their friends on the Algarve - the reaction was one of stunned disbelief and indignation.

The detectives appeared to be working on the theory that Mrs McCann killed her daughter by accident at their holiday apartment in Praia da Luz, and covered up the death by claiming she was abducted.

Test results from the Forensic Science Service in Birmingham received in recent days have apparently boosted this hypothesis. Speculation also surrounds forensic evidence from a hire car and the reaction of a sniffer dog on meeting Madeleine's mother.

Mr McCann's alleged role is not clear but sources said police believe he was an accessory to the killing.

Following an unprecedented world-wide campaign by the McCanns, aimed at getting their daughter back, that included embracing the Pope, JK Rowling and a host of footballers - the very idea of them being involved in their daughter's death was guaranteed to created shock waves.

Brian Kennedy, a great-uncle of the missing youngster, said the couple were "absolutely devoted" to Madeleine and their twins, and that no-one who knew them would believe they would hurt them in any way.

He added: "Their family and friends support them totally and we are sure everyone else who has been kind in their letters and prayers, and financially, will continue to believe in them and hope for a speedy and just outcome to the present situation."

Madeleine's aunt, Philomena McCann, said of the accusations: "Unfortunately this distracts from looking for the real perpetrator. My sister and mother went out to see them and help them pack, and to try and bring them home. My mum is completely beside herself - she's distressed and very, very upset as we all are.

"Can you imagine, the whole world has been watching Gerry and Kate for the last four months. Where do they hide their wee girl when they are in a foreign country where they just don't know people?

"The suggestions are just ludicrous."

Kate McCann's brother-in-law labelled the latest moves by the Portuguese police as "crazy".

John McCann said the idea that blood found in a hire car linked Mrs McCann to Madeleine's death did not make sense.

He said: "It seems highly implausible that after all the searches for Madeleine that had gone on she could be secreted into a hire car. I don't understand it, it makes no sense."

He also said there was growing frustration with the Portuguese police's methods, and called for them to get their investigation back on track.

"There's a degree of almost anger, it's more frustration. We just want them to get on with the real focus," he said.

"My wee niece is missing and it's not Gerry and Kate that are involved in this.

"Let's get back to the real reason. What's happened to that?"

Mr McCann also dismissed the idea that the little girl's mother had killed her by accident and hidden her body.

"It doesn't make sense if you look at the timelines on the night," he said.

"They were there with other people, they had children to put to bed - it's not feasible."

He said: "Everybody who knows Gerry and Kate know that to implicate them is ridiculous. What's being done about the man who was last seen with the child?"

He also complained the investigation was going too slowly.

Of the Portuguese police, he said: "They are about four months too late, is my honest opinion. I wish they'd got on with it earlier."

Mrs McCann's mother, Susan Healy, said the family were concerned that evidence may have been planted in order to incriminate Madeleine's parents.

She said: "She's (Kate's) very angry about her position. She knows perfectly well if this evidence exists, then it is proof there is somebody inside the police department or who had access to their apartment and their belongings who has planted this evidence."

Speaking from her home in Liverpool, Mrs Healy added: "Kate and Gerry are relying on the Portuguese police but there is an uncomfortable feeling that they are not necessarily looking outwards for Madeleine, but towards them."

Friends who dined with the McCanns on the night Madeleine vanished on May 3 said they were "totally appalled" at any suggestion that Kate McCann was involved in her daughter's disappearance.

In a joint statement, the group stressed their firm belief that Mrs McCann was innocent and said they would support the couple until "this nightmare is over".

"She is innocent. we know this because we are her friends, we were with her on the night, and we witnessed first hand the unimaginable grief Kate and Gerry suffered and continue to suffer," their statement said.

"We will support them until this nightmare is over. We also hope that this will not detract from the search for Madeleine, who remains missing."

The McCanns were having dinner with a group of seven friends from the UK in a tapas restaurant opposite the Algarve apartment from where the four-year-old, then three, vanished.

Among them were Dr Russell O'Brien and his wife Jane Tanner, who themselves have two young children.

Other diners there were Dr Fiona Payne and her husband David, a senior research fellow at Leicester University, and Mrs Payne's mother Dianne Webster, and Rachael and Matthew Oldfield - another doctor.

They knew the McCanns because Mr Oldfield and Mr McCann, a cardiologist, worked together at a Leicester hospital. Mrs McCann is a GP.