The mayor of Portland, Oregon, demanded U.S. Immigration and Customs Enforcement leave his city after federal agents launched tear gas at a crowd of demonstrators — including young children — outside an ICE facility during a weekend protest that he characterized as peaceful.

Witnesses said agents deployed tear gas, pepper balls and rubber bullets as thousands of marchers arrived at the South Waterfront facility on Saturday. Erin Hoover Barnett, a former OregonLive reporter who joined the protest, said she was about 100 yards (90 meters) from the building when “what looked like two guys with rocket launchers” started dousing the crowd with gas.

“To be among parents frantically trying to tend to little children in strollers, people using motorized carts trying to navigate as the rest of us staggered in retreat, unsure of how to get to safety, was terrifying,” Barnett wrote in an email to OregonLive.