MINNEAPOLIS -- Some demonstrators spray-painted obscenities on the walls of the Minneapolis Convention Center as wealthy donors gathered for a private fundraiser attended by GOP presidential candidate Donald Trump.

Other demonstrators also spit on Trump supporters and harassed them as they headed back to their cars after the event.

Trump made no public appearance Friday night on his first trip to Minnesota since winning the GOP nomination. Tickets ran from $1,000 per person to 100,000 per couple.

Dozens of protesters gathered outside. Police say there were no arrests or injuries, but some traffic had to be rerouted because of protesters blocking roads.

The demonstrators who harassed departing donors were not present earlier when the protest was peaceful, and many in the later group concealed their faces with scarves.