Reports that Madeleine McCann has been spotted in a city in Paraguay have been called in to question by investigators looking in to the sighting.

It had been reported that the missing girl, who would now be 12, had been seen in Areguá by a man claiming to be a British private eye.

Miraz Ullah Ali’s claims that she ‘was in the custody of a woman’ triggered a search involving local police divisions and Interpol with the Met Police also informed.

However, the credibility of the witness has since been called in to question.

Madeleine disappeared from a holiday apartment in the Algarve in 2007 when she was three years old and sightings have since been made in numerous countries including Portugal, Sweden, Belgium, Morocco and The Netherlands.

Commissioner Sanny Amarilla, deputy chief of one of the police stations said to be hunting the missing girl, had told The Sun an investigation would focus on neighbourhoods where there are foreign citizens, villas, and condos.

However, his claims have been greeted with skepticism outside the local police division.

Inspector Luis Ignacio Arias of Interpol in Paraguay questioned Ali’s authority, saying there is “nothing concrete” about him, but adding Paraguay’s National Police will launch an investigation.

Kate and Gerry McCann, who were also made aware of the sighting, say they have not heard of the investigator.

Sebastian Jara, also from Interpol, added: ‘We do not have anything I can add, except that we have begun to move with all our might , but for now we have nothing.

‘Areguá is a very large and very populated city and this research caught us by surprise.’