ALBUQUERQUE, N.M. — Albuquerque’s mayor said that a more than 10-hour protest over recent police shootings turned from peaceful into “mayhem,” as officers in riot gear clashed with hundreds of protesters who blocked traffic, tried to get on freeways and shouted anti-police slogans.

Mayor Richard Berry said Sunday that one officer was injured, rocks were thrown and at one point protesters trapped police in a vehicle and tried to break the windows, the Albuquerque Journal reported. An Associated Press reporter saw gas canisters being thrown outside police headquarters and Albuquerque police and Bernalillo County sheriff’s deputies charging at the protesters late Sunday, which mostly dispersed the crowds.

The number of protesters dwindled to fewer than 100 before midnight, and three or four people were arrested, the newspaper said.

Multiple messages left for the Police Department weren’t immediately returned. Video by KRQE-TV showed people being led away in zip-tie restraints, but it’s unclear if those people were arrested or if any protesters were injured.

“We respected their rights to protest, obviously,” Berry said, “but what it appears we have at this time is individuals who weren’t connected necessarily with the original protest.