PHOENIX — Calling their actions “disgusting, aggressive and violent,” immigrant and civil rights activists on Wednesday railed against police for their response to a protest that turned unruly after President Donald Trump held a rally in downtown Phoenix.

Phoenix police Chief Jeri Williams has defended her officers, saying they used appropriate force and acted professionally to disperse a crowd after gas was thrown at police. Police say four people were arrested, including one for an unrelated warrant. The only reported injuries were related to heat symptoms.

Thousands of people protested Trump for hours in the scorching Phoenix heat without incident. It was after the rally ended and most people were leaving that a small group of men began throwing water bottles at police, according to Antonio Bustamante, an attorney who was observing the protests Tuesday.

Police say protesters threw tear gas and other objects at police, a claim organizers deny.

“The city failed us yesterday,” said Francisca Porchas of Puente Arizona, one of the groups that organized protests yesterday.

Williams said in an interview with radio station KTAR that officers were deliberate and waited to respond after they were struck by items.

“I absolutely give my folks an A-plus,” she said.

Maricopa County Attorney Bill Montgomery also stood by police, saying Wednesday that officers “swiftly and decisively dealt with small fractions of individuals who attempted isolated actions of violence” while protecting public safety and free speech for law-abiding individuals.

Others have called for a thorough review of events.

U.S. Rep Ruben Gallego, a Democrat who represents downtown Phoenix, is asking the city to hold a community meeting to provide a detailed account of what happened.

Phoenix Mayor Greg Stanton, also a Democrat, said he is committed to a “thorough and transparent” review by police of the events that unfolded following the rally.

Stanton said in a statement that the organizers were peaceful but that a few people threw tear gas, bottles and rocks at police, prompting officers to use pepper spray.

Activists say they have filed a complaint and plan on attending a city council meeting next week to voice their anger at police.

“We were terrorized, we were attacked by the Phoenix Police Department. They came in as if this was a war zone,” Puente organizer Carlos Garcia said.