I’m violating my own rules here, but the media are not keeping up with developments, so I’m having to wing it.
These are chemical containers being unloaded from both helicopters. The commenters on Reddit are far more qualified than I am to extrapolate, but at the base level, the government flying them into the middle of a city is … troubling.
I can’t see the Reddit posts, but as an Army veteran - my money is on them using CS gas. The stuff really sucks, and can incapacitate you if you’re not ready to counter it.
Apologies for the Reddit links; they were embeds, so I had no other option.