As Maddie's anguished parents - heart consultant Gerry McCann and GP Kate, both 38 - tried to carry on with their Algarve holiday for the sake of their other two toddlers, senior investigator Guihermino Encarnaca said: "There is a prime suspect and there is a portrait sketch of the suspect.

 

"I am not going to reveal it or give more information at this stage because it may put the girl's life in danger.

 

"But I do believe she is still alive."

 

Mr Encarnaca who is investigating 30 "strong" leads, added: "As for the reason she was taken - in Portugal kidnap is not just for money but can be for sexual abuse."

 

But relatives of the distraught parents from the upmarket village of Rothley, Leics, insisted that police had bungled the first few critical hours of the investigation at the luxury Mark Warner Ocean Summer Club resort in Praia da Luz.

 

As hundreds of officers, local Portuguese, British holidaymakers and even expatriate Brits who drove from other parts of the Algarve joined a desperate search of surrounding countryside, Gerry's sister Philomena McCann said: "The police were doing very little after Maddie vanished.

 

"Gerry and Kate were left on their own and Mark Warner staff had to organise the searches. The police did nothing for hours and hours."

 

And when Maddie's godmother and great-aunt, Nora Healy, was asked what she thought about the police response she raised her eyebrows and said: "Well, it upped a gear when the British ambassador arrived."

 

The relatives who had flown to the Algarve to comfort the distressed parents also hit out at suggestions that Gerry and Kate had not been looking after their children properly.

 

Blonde blue-eyed Maddie, four next Saturday, was snatched from their holiday apartment on Thursday evening as she slept with her brother and sister, two-year-old twins Sean and Amelie.

 

The McCanns, who had been enjoying a £1,600 week-long break with nine other doctor friends, were dining at a tapas bar 40 yards from their apartment and were checking the children every half hour.

 

Great-aunt Nora said: "Please don't say they weren't watching them. They could see the apartment from where they were and they were checking them.

 

"These are doctors, these are intelligent people."

 

And retired headmaster Brian Kennedy - the uncle of Maddie's mumwho lives in the same village - said: "The children were left only in the sense that when you put your children to bed you don't stay in the room all night. They are highly responsible parents who are devoted to their family."

 

All three children were conceived after Kate had IVF treatment.

 

Gerry's sister Philomena added: "They love Maddie so much. She is the centre of their universe. Maddie is such an integral part of the family and a loving big sister to the twins. She is their Pied Piper.

 

"She is their little princess and the focus of everything for the whole family."

 

Mr Kennedy and his wife Janet attended a prayer meeting for Maddie last night at Rothley parish church. He added: "We fear the worst but we are hoping for the best."

 

British Ambassador John Buck has been with the family throughout their ordeal. Yesterday three family liaison officers from Leicestershire Police flew in to help the parents deal with the Portuguese authorities.

 

Gerry and a relative were allowed back in the apartment briefly to collect a suitcase of clothes and the children's bucket and spade as the massive search for Maddie continued.

 

Manchester manDave Shelton, 38, who has lived in Praia da Luz for 16 years running an air conditioning company, has been co-ordinating the hunt.

 

He said: "I came here first on Friday morning, I speak a little Portuguese and was helping police knock on the doors of all the apartments. Then people just started coming out of the woodwork saying 'Lookwe've heard, what can we do to help?'"

 

Using a map provided by the local mayor and aided by extra maps downloaded from the internet, around 800 people have so far taken part searching an area from the resort to the next village of Quatro Estradas around three miles away. Meanwhile Senor Encarnaca, head of the local Policia Judiciari - the Portuguese CID - denied his officers had been slow to respond.

 

He said local uniform cops - the Guardia Nacional Republicana or GNR - had been on the scene within five minutes of a call at 10.40pm and that his officers were there before midnight coordinating searches.

 

He insisted he was happy with the parents' account of the tragic events and they were not suspects.

 

But GNR Captain Marco Henriques said Maddie's parents could face prosecution for leaving a child once the investigation was completed.

 

Local mayor Julio Barosso said: "We will do all we can to help find this little girl.

 

"We are hoping Madeleine will come back to her parents and that England can breathe again.

 

"I hope from the bottom of my heart that this story does not have a bad ending."