San Diego police arrested 35 people Friday during protests that followed Donald Trump's rally here, drawing praise from the presidential candidate on Twitter.
"Fantastic job on handling the thugs who tried to disrupt our very peaceful and well attended rally. Greatly appreciated!" Trump wrote.
At least 18 people received medical attention. San Diego police reported no property damage during the protests, which drew an estimated 1,000 people.
In the Gaslamp Quarter, police declared an unlawful assembly because of violence about 4:40 p.m., announcing in Spanish and English that crowds needed to disperse. Officers with riot gear were moving among the crowd.
By 6 p.m. police appeared to have restored order.
Several people threw plastic bottles, some of which hit police officers, near Petco Park on L Street between 5th and 6th avenues. Also nearby, a man burned a Trump "Make America Great Again" hat among a crowd.
Tensions grew and several small fights broke out in the same area when anti-Trump crowds started to mix with his supporters.
TV news video showed some protesters throwing objects at a line of police officers outside the San Diego Convention Center while Trump spoke inside. At least one protester tried to climb up to where the officers were. The video showed officers using batons to push him back into the crowd.