A police force has said it cannot release footage of its officers' involvement with a man who died hours after being released from custody until an investigation has concluded.
South Wales Police said CCTV and body-worn video had been handed to the Independent Office of Police Conduct (IOPC), which is reviewing police contact with Mohamud Mohammed Hassan.
The 24-year-old was arrested on Friday evening on suspicion of a breach of the peace after reports of a disturbance at his home but released the following morning without charge.
He was found dead at the same property later on Saturday evening, with his family claiming he had been assaulted while in custody, but police say there are no indications of excessive force used by their officers.
On Wednesday, crowds of protestors gathered for a second day outside Cardiff Bay police station where Mr Hassan was detained, demanding that video footage of his arrest and time in custody be made public.
More than 150 people attended the protest outside Cardiff Bay Police Station, carrying placards and chanting outside the station.The road outside the police station leading from Cardiff Bay into Grangetown was blocked for more than an hour.Messages on the placards read "Justice for Mohamud" and "All Lives Won't Matter Until Black Lives Matter".
But the police force said in a statement that as the material had been passed on to the IOPC for its independent investigation, it could not be released at present.
A spokesperson said: "South Wales Police has provided all relevant CCTV footage and body-worn video to the IOPC who are now conducting an independent investigation into police contact with Mohamud Hassan prior to his death in Cardiff on Saturday.
"Therefore the footage cannot be released by South Wales Police while the IOPC is investigating.
"Our thoughts and condolences are with the family and friends of Mr Hassan and we acknowledge the impact that his death has had on the wider community.
"We are fully co-operating with the IOPC investigation and are providing them with all of the information and material they have requested."
The IOPC's director for Wales, Catrin Evans, said the investigation will look at the level of force used by officers, but that early indications following post-mortem showed no physical trauma to explain his death.
His aunt, Zainab Hassan, told ITV News she wanted him to be remembered as "the happy, loving young man that he was."
She saw Mr Hassan following his release on Saturday with "lots of wounds on his body and lots of bruises".
On Tuesday afternoon, a marching crowd of protesters chanted "no justice, no peace" as they made their way to the police station, and held up signs that read "Black Lives Matter" and "stop police brutality".
Welsh First Minister Mark Drakeford described reports of Mr Hassan's death as "deeply concerning", while Plaid Cymru leader Adam Price described it as "a deeply harrowing case".