Madeleine McCann: Hidden cellar discovered during search of allotment rented by main suspect

A hidden cellar has been discovered at an allotment being searched in relation to the disappearance of Madeleine McCann.

McCann went missing from an apartment in Praia da Luz, Portugal in May 2007 at the age of three. Her disappearance has gripped the world ever since and is back in the headlines after British and German authorities identified a suspect earlier this year.

As part of their investigation, police have begun excavating an allotment near Hanover in Germany once rented by Christian B, the German suspect who is currently imprisoned for unrelated sex crimes.

British and German media are now reporting that a cellar had been found on the site and it is believed to have once been a part of a garden house.

According to a neighbour who has spoken to the BBC, the sex offender rented the plot in 2007 and wanted to insulate a shack on it. A cellar is reported to have been below that structure. 

The neighbour went on holiday in July 2007 and when they returned in August, the structure was gone and he never saw the suspect again, the BBC says. 

Authorities at the site near Hanover have been using excavators, ground radars, sniffer dogs and drones. The airspace above the allotment has also been shut off. Prosecutors won't say what the teams are looking for. 

In June, London's Metropolitan Police appealed to the public for information after identifying the suspect, who had lived in the Praia da Luz area "on and off" between 1995 and 2007. The authorities wanted information about two vehicles and a phone number used in the area.

Since then, further information has been reported about the police investigation and Christian B, including his suspected links to other missing person cases and the search of a dilapidated factory in Germany where the man spent time.

While British authorities continue to treat the investigation as a missing person one, German prosecutors believe the girl died soon after allegedly being kidnapped.