All of the above advice sounds good but I have a sneaking suspicion that somewhere in my dark strata past I have been described as disruptive and aggressive.
I would consider holding out an olive branch to these people and asking them what they want – force them to either sit down quietly and discuss issues in a forum where the facts can be presented and explained or reveal themselves to be more interested in spoiling tactics rather than finding solutions.
Community Justice Centres provide a free mediation service where you can discuss these things on neutral ground. If they fail to engage, that's more ammunition for when they really start stirring things up.
You might also adopt a set of standing orders from a book like this which would include rules such as one person can't speak again until everyone who wants to speak has had their say.
Personally, I would get the chairman to lay down the law at the beginning and say that a) anyone who abuses the privilege of being allowed to speak will probably not be allowed to do so in the future and b) if anyone disrupts the meeting by their bad behaviour it will be adjourned and the reason for the adjournment will be stated in the minutes (notwithstanding Whale's valid observation that infamy may be exactly what they desire).
As a last resort, I would hold your discussions elsswhwew and only convene the meeting to formally approve the items on the agenda – although that is almost certain to inflame emotions. But it does mean you could be in and out of the formal meeting withing minutes. Best of luck.