At least a dozen people have been detained in the US city of Baltimore for allegedly breaking a nightly curfew.
One man was apprehended with pepper spray, before being handcuffed on the ground. He was later heard moaning, as police called for a medic.
The curfew was brought in the wake of violent protests, sparked by the death of Freddie Gray, a black man who died after being injured while in police custody.
Earlier on Saturday, thousands of people took to the streets as anger over his death turned to hopes for change.
Six police officers have been charged in connection with the case, a cause of celebration in Baltimore.
Campaigners say they want to see justice served not only in the city, but also in other US communities – where they feel minorities are unfairly targeted and treated by police.