Madeleine McCann: German authorities 'ignored warnings over suspect'

German media are focusing their attention on whether the federal police ignored warnings in 2013 from a local force that was on the trail of the Madeleine McCann suspect Christian Brückner for a variety of crimes, including child abuse and drug dealing.

Investigators in Braunschweig who had been closely monitoring Brückner believed he should be viewed as a key suspect in the girl’s disappearance. But their alert was reportedly ignored by Germany’s Federal Criminal Office, the BKA, according to Der Spiegel, which has a team of 10 reporters working on the case.

Brückner was named as a possible key suspect following information received from several tipoffs out of the 500 calls made after the broadcast of German TV’s Crimewatch equivalent, Aktenzeichen XY, in 2013, in which Gerry and Kate McCann appeared in person to appeal to the public for information.

Related: Why Madeleine McCann was never just another 'lost child' story | GilesTremlett

Brückner’s name was followed up by police in Braunschweig, where Brückner was registered as living and was well known due to his extensive criminal history. But the resulting report by the Braunschweig investigators was apparently not followed up, “much to the incomprehension of the local investigators”, according to Spiegel.

Christian Hoppe, an investigator for the BKA, told last Wednesday’s edition of XY, which made a renewed appeal to the German public based on fresh circumstantial evidence, which placed Brückner in Praia da Luz at the time of the disappearance, that there had been a lack of concrete evidence to merit a follow-up.

“The information we had then was not sufficient for an investigation, and certainly not for an arrest,” he said.

The programme did not name Brückner, whose name subsequently emerged in media reports.

The development comes as reports on Friday said authorities were looking into connections with the disappearance of a six-year-old German boy in Portugal in 1996.