British detectives investigating the 2007 disappearance of Madeleine McCann said they are looking for a man suspected of carrying out a series of sexual assaults on young girls staying in Portuguese holiday villas between 2004 and 2010.

McCann, then aged three, went missing from her bedroom at the Praia da Luz holiday resort in the Algarve while her parents were dining with friends at a nearby restaurant, leading to a global search that gripped the world's media.

London police, who started a review of the case in 2011 and began their own investigation last year, said on Wednesday that they were looking for more information about 12 crimes committed in Portuguese holiday resorts.

In four cases between 2004 and 2006 a man sexually assaulted five white girls, aged between 7 and 10 years, in their beds, police said. Two of the 12 offences were committed in Praia da Luz.

"These offences are very serious and no one has been charged in connection with them," Andy Redwood, the senior investigating officer, said in a statement. "We also need to eliminate this man from our enquiries and ascertain whether these offences are linked to Madeleine's disappearance."