Phoenix police have an arsenal of non-lethal weapons at their disposal to break up crowds.
Here are a few that were used during the chaos Tuesday outside the rally for President Donald Trump.
Smoke canisters and tear gas
Officers rolled several canisters that emitted clouds of smoke or gas. Smoke is just visual; tear gas is a chemical that irritates the eyes, nose, mouth, and lungs of people nearby. Technically, “tear gas” is not a gas – it’s made entirely of tiny, solid particles.
Visually, the canisters and clouds are virtually identical, said retired Tempe SWAT officer Kevin Boontjer.
“They’re typically the same size canister. The only thing that’s different are the markings,” he said.
The similarities are intentional. Officers will often deploy smoke first, hoping to scare off members of the crowd without exposing bystanders or themselves to the unpleasant, and sometimes harmful, effects of gas.
“We just want to get people out of there. So if we think smoke is going to achieve that objective, we'll throw some canisters of smoke out there, [and] people think it's gas. If we get rid of half our crowd or more, we've achieved our objective, right?” he said.
Also referred to as flash grenades, these diversionary devices produce a bright flash and loud explosive sound. The sound is about 170 dB: about 32 times louder than a rock concert.
Phoenix police used at least two types of pepper-spray projectiles Tuesday night. One is commonly referred to as a pepper ball. These rounds look like paintballs and contain oleoresin capsicum, the active ingredient in pepper spray. The rounds are launched from a modified paintball gun.
In the now-viral case where a protester got hit with a round between the legs, officers used a larger, but similar, launcher.
“It appears that the projectile that struck that particular person was one of the larger pepper balls that are disbursed from a different-style system,” said Phoenix police spokesman Sgt. Jonathan Howard.
[RAW VIDEO: Police, mayor talk about post-rally violence]
Enhanced video shows the gas round had an orange tip, and appears to be what’s called a sponge round. These rounds can contain either pepper spray or dye to mark protesters. In this case, it appeared to contain pepper spray.
“That is similar to a pepper ball gun, it's just a larger round,” said Boontjer. “It's probably out of a 37 mm or 40 mm gun.”
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