Chief Inspector Olegario de Sousa said that police were doing "everything they could" to locate the girl, with more than 200 square kilometres searched by local police and national guard so far, while aerial and navy searches have also been conducted.
Portugal's legal system restricts police from revealing many details of criminal investigations that people in Britain have become used to being told, and Ch Ins de Sousa reiterated tonight that his hands were tied in what he could and could not tell journalists.
"I will not speculate on possible motives," he said in response to media questioning on claims that police were investigating new CCTV images at the Praia da Luz resort, although he did confirm that no members or friends of Madeleine's family were under suspicion.
The police chief also revealed that items of clothing presented to searchers yesterday did not belong to the child.
Yesterday, Madeleine's parents Gerry and Kate McCann, said they were 'staying positive'; a week after their daughter disappeared from an apartment bedroom.
"We are grateful to all of those currently taking part in the search for our daughter Madeleine," a statement read by Alex Woolfall, a representative of the operator of the resort where the family were staying, said.
"At present, we are channelling all of our emotions and all of our efforts into the steps that are being taken to secure Madeleine's safe return."
Mrs McCann today attended church services in the Algarve as she has done all week, with the mother of three appearing to need support as she clutched Madeleine's favourite cuddly toy.
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