Updated at 12:49 a.m. ET Aug. 23

Police in Phoenix deployed gas, flash-bang grenades and pepper spray to disperse protesters shortly after President Trump wrapped up his rally at the city's convention center.

The gas canisters were fired after someone among the protesters threw rocks and water bottles at the police, according to Phoenix Police Department Sgt. Jonathan Howard. The police action appeared successful — photos of the streets around the venue show that the crowd of protesters had largely diminished. The police department ordered everyone to leave the area.

Shouting matches, though, are happening in some areas.

Earlier, there were reports that another group of protesters had left the scene at the convention center and were marching toward the state capitol.

While the president was speaking, several dozen people outside the venue were taken to the hospital after suffering from heat exhaustion. Phoenix has experienced triple-digit temperatures all day.

Before Trump's rally, The Associated Press reported there had been some minor scuffles and shouting matches between Trump supporters and critics as people stood in line to get into the convention center.

NPR affiliate KJZZ's Michel Marizco and Carrie Jung report that protesters yelled "shame on you" at attendees entering the center.

Protesters also chanted "Donald Trump has got to go" and "this is what democracy looks like."

For most of the night, the protests remained mostly calm and police kept both sides separated.

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