The ‘habeas corpus’ request, which was submitted by lawyers for Mendes, the leader of Juventude Leonina, a Sporting fans club, argued that a decision by the Lisbon appeal court to hold him on remand was “illegal”

The case centres on the illegal entry by a group of self-described Sporting fans to the training academy in Alcochete, south of the River Tagus, on 15 May 2018, and the physical assault of several professional footballers and members of staff.

On 17 May, Mustafá - one among 44 suspects in the case - handed himself in at a police station in Charneca da Caparica, Almada, after the Lisbon appeal court ordered that he be held on remand.

He had previously been free, with the obligation of reporting daily to the authorities, after posting bail of €70,000, under a court ruling of 15 November 2018. But public prosecutors successfully appealed that ruling.