Searching for Madeleine McCann on Thursday resumed the place where the three-year-old boy disappeared from Praia da Luz, Portugal, 18 years ago.

German and Portuguese investigators must look for evidence related to her disappearance by Friday, but so far there have been no obvious signs of any significant discovery.

Officials searched the 21 square kilometers (8.1 square miles) of ruins in the place where she disappeared and the main suspect of German investigators, Christian Brückner, where he had lived at the time.

The 48-year-old was sentenced to jail in Germany for irrelevant rape cases, but could be released as early as September.

Madeleine McCann, three, disappeared from an apartment in Algarve while on vacation with her family in May 2007.

Her disappearance is one of the most watched cases of missing persons in the world.

Madeline's case was initially handled by Portuguese authorities with the help of the Metropolitan Police.

However, German police took the lead when they identified Bruckner as the suspect in 2020.

He was known to spend some time in the same region in Portugal between 2000 and 2017.

German police suspected him of murder. British police continue to investigate the case as missing persons.

Bruckner repeatedly denied any involvement and had no charges against Madeline's disappearance.

Portuguese prosecutors approved a European arrest warrant allowing German teams to conduct the latest search on private land.

Excavators and professional equipment were brought in to help with the bushes and abandoned buildings on Wednesday.

The last search was conducted near the 2023 Barragem Do Arade Reservoir, as Brückner has his own photos and videos in the area.

Madeleine is missing, her parents have dinner with friends in the restaurant, not far away, while their three-year-old daughter and young twin siblings fall asleep in the ground apartment.

Last month, Kate and Gerry McCann commemorated the 18th anniversary of her disappearance, saying they were “unwavering in the stones of determination without hesitation.”

Staff from the Find Madeleine campaign said they would not comment in the "active police investigation."

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