PORTLAND, Ore. (KOIN) — Mayor Ted Wheeler said mistakes were made when police responded to a “Not My President’s Day” protest in downtown Portland Monday and forcefully took some people into custody.

A total of 13 people were arrested after a group of protesters left the sidewalk and spilled into the street at SW 3rd Avenue and Madison Street.

Police said the protesters were blocking traffic, and despite warning them to clear the street for 20 minutes, some still refused to move.

Video captured officers in riot gear forcing some protesters to the ground, including a 66-year-old woman whose face was scraped and bloodied as she was arrested.

On Monday night, a small group of protesters gathered outside Mayor Wheeler’s house to voice their displeasure with how police handled the daytime protests.

Less than a day later, the mayor released a statement acknowledging that mistakes were made during Monday’s event, and promising to work with Police Chief Mike Marshman to “discuss how we can best reduce tensions moving forward.”

“Portland has a strong history of activism and peaceful protest. But the message is being undermined because of ongoing tensions between protesters and police,” Wheeler wrote. “We cannot afford for this type of conflict to occur when we have so much other work to do in this city that requires us all to work together.”

Read Mayor Ted Wheeler’s full statement below: