BOULDER, Colo. (AP) — Several people were injured and some may have been set on fire at an outdoor mall in Boulder, Colorado, police said. Police said a man was taken into custody in the attack that the FBI immediately described as an act of terror.

Boulder Police Chief Steve Redfearn told reporters Sunday evening that it was too early to discuss a motive but that witnesses were being interviewed.

“It would be irresponsible for me to speculate on motive this early on,” he said.

The attack took place at a pedestrian mall where demonstrators had gathered to call for the release of hostages who remain in Gaza.

THIS IS A BREAKING NEWS UPDATE. AP’s earlier story follows below.

BOULDER, Colo. (AP) — Law enforcement and FBI agents were responding on Sunday to what the FBI described as a “targeted terror attack” in Boulder, Colorado.

“Our agents and local law enforcement are on the scene already, and we will share updates as more information becomes available,” FBI Director Kash Patel posted on social media.

Boulder Police said they were evacuating several blocks of the typically popular pedestrian mall area, saying that there were “several victims” in the attack without providing further details.

Colorado Gov. Jared Polis said in a statement that he was “closely monitoring” the situation, adding that “hate-filled acts of any kind are unacceptable.”