How do riot police handle the odd gunman?

Factual Questions
1

In Ireland during the Troubles, riots were common and would sometimes involve small numbers of rioters or IRA members firing guns at the police. With the protests in Hong Kong, Europe and the US, I’m wondering how police handle pot shots being taken at them during either a riot, otherwise peaceful marches or protests which are halfway between a peaceful march and a riot (like WTO, Antifa and alt-right protests).

For example, let’s say someone at something similar to the Unite the Right rally or Gilets Jaunes protest sniped at police, how would police deal with that, especially if the shooter took care to be sneaky and only took single long-range shots from narrow visibility angles in concealed positions? How would police differentiate between real shots that pose deadly danger to them vs faked shots aimed at provoking an overreaction?

Don’t need answer quick.

2

Well, I don’t know any details but I can be sure of 2 things in the US:

  1. the police would stop worrying about the rioting crowd, they would be dispersed quickly even in the unlikely event they hung around once shots were fired,
  2. there is no such thing as a fake shot.
3

They wouldn’t. There is no difference.

4

How would the rioters/protesters be dispersed? I’ve seen potshots be taken during an NI protest in Derry where journalist Lyra McKee died and the protesters didn’t disperse: https://www.youtube.com/watch?v=0dcmLDpdD8U
Irish protesters seem to like their Molotov cocktails but they could graduate to pipe bombs.
Fake shot: Something can be made to sound like a gunshot without requiring a gun, especially in a noisy environment with wonky acoustics like city streets.

5

Typical non-lethal crowd dispersal means include water cannon, tear and pepper gas, rubber bullets/pellets, sonic cannons, etc. You have probably seen such scenes on the news.

6

… all of which is dropped the moment the shooting starts. Cops and soldiers aren’t stupid: they’re not going to bring a water cannon to a gunfight.

7

Hey, you’re Israeli so you must know rather a lot about this. When a shot rings out in the middle of a stone-throwing, tire-burning riot, how do the IDF soldiers handle the stone-throwers and unarmed protesters?

8

Honestly, I’ve never heard of protesters not scattering the moment shots are fired. They’re not stupid. But if it does happen, you pull back to a protected position and return fire.