An inquiry into the death of a man in police custody will look at CCTV footage of his arrest and his arrival at a Lancashire police station.
The Independent Police Complaints Commission (IPCC) is investigating the death of Nadeem Khan in Burnley.
The 28-year-old was arrested in Brierfield after reports of windows being smashed and violent behaviour.
IPCC officials said post-mortem tests on Mr Khan's body had not determined his cause of death.
But John Crawley, IPCC Commissioner, said it had "answered certain crucial questions for our inquiry".
"It has confirmed that he had suffered no serious trauma injuries and had no natural disease," he said.
"It found minor abrasions and bruising which were consistent with the independent witness and police accounts we have assembled so far."
He said Mr Khan had been seen on Saturday morning "engaged in breaking glass in windows and other violent behaviour, and then violently resisting arrest when the police attended."
Toxicology reports would not be ready for a number of weeks, he added.
Mr Khan became ill at Burnley Police Station and was taken to the town's general hospital where he was pronounced dead at 1030 BST on Saturday.
Mr Crawley said investigators had been at the scene throughout the weekend.
"They have met members of Mr Kahn's family to explain our role, which is to provide the reassurance, to family and community alike, that a fully independent investigation of the police's handling of this incident is already well under way.
"This has been a stressful time for all those involved in this incident," Mr Crawley said.
"It is always a shock when someone as young as Mr Khan dies so suddenly, and my thoughts are with Mr Khan's family."