BLOOMINGTON — A mass of demonstrators chanting, “Black lives matter,” converged in the Mall of America rotunda Saturday as part of a protest against police brutality that caused part of the mall to shut down on a busy day for holiday shopping.

Bloomington police said 25 people were arrested, mainly for reasons such as trespassing. Commander Mark Stehlik said he was not aware of any injuries or property damage.

Mall representatives had warned protesters in advance that they could be removed, arrested and banned. The mall’s management issued a statement Saturday saying it was “extremely disappointed” that protest organizers ignored the policy banning political protests.

About 30 minutes after the planned protest began, a final warning to disperse was given, and police in riot gear began clearing the rotunda.