Washington DC Mayor Muriel Bowser said protesters in the city brought “tools and supplies” with them last night.

“Well, we know that we have people that came here with tools and supplies, and they re-upped their supplies. They went to different parts of the city, so we think there was a mix of people here but certainly people here who do this type of protest demonstration,” Bowser said will speaking on NBC this morning.

NBC’s Craig Melvin asked her if they were “professional protesters and demonstrators.”

“Well, we’ve seen some of these tactics before, so we know that they were among the groups here,” she said, describing the tactics as “the types of tools they used, restocking, setting fires here and there to draw in the police to various locations.”