For the first time in more than 100 nights of protests and numerous riots in downtown Portland, the National Guard has been sent into the city.

A dozen people were arrested after two groups of protesters converged in downtown Portland Wednesday evening, with one group going to Waterfront Park and the other blocking the Morrison Bridge and vandalizing small businesses and churches.

That brought a swift response from the Unified Command of the Oregon State Police, the Multnomah County Sheriff’s Office and the Portland Police Bureau. The National Guard was activated around 7 p.m. A riot was declared around the same time, KOIN reports.

Several people had been arrested in downtown Portland by 9 p.m., according to Unified Command. Authorities said they arrested a man accused of throwing a Molotov cocktail — which was later determined to be a firework — at officers. That man was wearing a tactical vest and had a loaded rifle with additional magazines, an improvised explosive device, a knife and cans of spray paint, Unified Command said.

Law enforcement said they had also seized commercial-grade fireworks and hammers throughout the night.

The evening began with an election protest and quickly evolved into roadways being blocked and widespread destruction.