I am no expert in safety or security, but my first questions when considering a dangerous situation are "What do I do?" "How do I protect myself and others? What will minimize damage or injury? That's how I get a head start on overcoming fear to be sure I can take immediate action in an emergency.
I've never before considered what to do if a flash mob should erupt. I didn't find a lot in my searches, but here are some articles about protecting oneself from violence during riots that may be useful to help people prepare themselves in advance.
If anyone has links to expert or official advice and instructions for keeping safe in times of civil unrest, please add them in the comments.
wikiHow's "How to Survive a Riot" in the Travel Safety & Security category seems to offer VERY useful advice, pointing out that "riots can break out anywhere", noting that angry mobs have rioted after "college tuition increases, soccer games, institutionalized oppression, death caused by police, editorial cartoons, and a movie star's death". The article lists 8 steps, with detailed notes under each. Below are condensed excerpts:
1. Be prepared. If you know an area is ripe for a riot but you can't avoid traveling there, take some simple precautions to help protect yourself.
*First, be prepared for the worst; the unexpected can happen at any moment. Crowds are dangerous when they're in an ugly mood and normally placid people can turn frenzied just by being in the presence of other frenzied people.
*Wear dark clothes that minimize the amount of exposed skin when going out. Do not wear clothing that could be interpreted as military or police wear in any way; avoid wearing anything that looks like a uniform.
*Take a motorcycle helmet with you. If bricks or other large items are being thrown about, at least you protect your vulnerable head.
2. Remain calm. ... Avoid confrontation by keeping your head down.
# Walk at all times. If you run or move too quickly, you might attract unwanted attention.
3. Get inside and stay inside. Typically riots occur in the streets or elsewhere outside. Being inside, especially in a large, sturdy structure, can be your best protection to weather the storm. [B]e on the lookout for signs of fire. If the building is set on fire get out quickly.
4. Stay on the sidelines. If you're caught up in a riot, don't take sides.
*Try to look as inconspicuous as possible, and slowly and carefully move to the outside of the mob.
*Stay close to walls or other protective barriers if possible but try to avoid bottlenecks.
5. If you're caught up in a car, stay calm. Remain inside the car unless your car becomes a focus for the riot, in which case it risks being torched, smashed or rolled over. Calmly and swiftly leave it behind and get to safety if that happens.
6. Use the social media to alert you as to where to stay away from.
7. Avoid being hit by riot control chemicals or weapons.
8. Move away from the riot. ....in most circumstances it's better to move out of a riot slowly.
* If you run, you will draw attention to yourself, so it's usually best to walk.
* It can also be dangerous to move against a crowd, so go with the flow until you are able to escape into a doorway or up a side street or alley.
The article also includes lists of tips and warnings. Be sure to read it all at wikiHow. There's a related article on wikiHow titled "How to Avoid Danger During Civil Unrest" that offers useful advice as well.
The Travel Safety Hub on WorldNomads article "Safety Advice: What to do about Political instability" from 2008 lists recommendations for avoidingdemonstrations and keeping safe during disturbances, including:
If caught in a civil disturbance
* If you find yourself caught up in a demonstration keep to the edge of the crowd where it is safer. Try not to be identified as being one of the demonstrators by keeping well away from the leaders/agitators
* At the first opportunity break away and seek refuge in a nearby building or find a suitable doorway or alley and stay there until the crowd passes
* When leaving the fringe of the demonstration just walk away – don’t run as this will draw attention to you
* In the event that you are arrested by the police/military do not resist. Go along peacefully and rather contact red24 or your embassy to help you resolve your predicament
* If you are caught up in the crowd, stay clear of glass shop fronts, stay on your feet and move with the flow
* If you are swept along in the crush, create a space for yourself by grasping your wrists and bracing your elbows away from your sides; bend over slightly – this should allow you breathing room
* If pushed to the ground, try to get against a wall and roll yourself into a tight ball and cover your head with your hands until the crowd passes
* Remember to keep calm – the crowd should sweep past in a short space of time
* If shooting breaks out, drop to the ground and cover your head and neck, and lie as flat as you can "
This article from last year on a progressive/liberal website describes how one couple used Twitter to track a mob's movement and to attempt to build a counter-stream of re-tweets urging calm: "How the Twittersphere Helped Keep Oakland Safe During Riots"
Here are two articles from the Christian Science Monitor on how social media can draw a crowd - or a mob:
Social media mayhem: when flash mobs go from benign to malign `includes a girl who used Facebook to invite her friends to her birthday party - and 1,600 people came to her house.
'Flash robs': How Twitter is being twisted for criminal gain' outlines how gangs of dozens are scheduling shoplifting events and other criminal activities.
Our community Neighborhood Watch programs and Volunteer Fire Departments are good places to start working with our local authorities and first responders to plan ahead to help our communities avoid or respond quickly, firmly and effectively to these kinds of events.
January 20, 2017 UPDATE: Here is a great article from Donald Sensing on what to do - and what NOT to do - in case shooting breaks out: http://senseofevents.blogspot.com/2017/01/what-not-to-do-under-gunfire.html