There are reports that British police want to use radar equipment to scour three sites.
Metropolitan Police Assistant Commissioner, Mark Rowley, said he would be unable to provide details of the search activity.
BBC News reported that a letter was sent to media editors, urging them to avoid speculation about excavation work. Mr Rowley reportedly told the British media to “think carefully” about information they published.
The latest development comes just two months after police announced they were looking for an intruder who sexually abused five girls in Portugal between 2004 and 2006.
Madeleine’s parents, Gerry and Kate McCann, who have been actively involved throughout the seven-year investigation, have never given up hope that their daughter is alive.
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