Make information available. Nothing that would violate privacy policies or put your legal case at risk, but other than that, talk to your members about what happened. Be careful to distinguish facts from analysis, but share both -- what happened, how did you get here, what went wrong?
Be responsive and not defensive. When a community member raises an issue, respond quickly with what you can say and promise (and deliver) more later if you need more time. And that response should serve the community; being defensive will hurt you. If people wait days or weeks for any response at all, they'll assume you don't care or are hiding something. Don't wait for the polished final response to say anything at all.
Admit your (you plural -- the representatives) part in this. You didn't swindle the community, but it happened on your watch. You thought there was sufficient oversight (or that trust was warranted) and it turned out you were wrong. Own up to that. Use that as an entry to a discussion about operational changes.
Try to focus the conversation on action, not witch-hunts. Yes, your previous board did some terrible things and your members need to know that you're doing all you can to hold them accountable, but what you really need the community to focus on is moving forward -- adjusting your programs to require less money (at least in the short term) and fixing your operating procedures to make this less likely to happen again.
Ask for their help. You're going to get it anyway, it sounds like, but make it clear up front that you don't consider this an "us vs. them" situation. You want to work with the members of the community to fix the problems.
Between meetings, communicate frequently. Send out summaries of meetings so that people can see that you heard their concerns.
If your governing documents don't cover your current situation (entire board removed), the community is going to have to improvise to seat a new board. Talk with them about how to solve the one-time problem -- maybe you want a direct election by the membership for a one-year board term, for example. If a new board is put in place and the members don't feel they had a voice in it, that will dominate member discussions.
The board we had to sue got almost all of this wrong. They declared a financial emergency (with unpopular emergency remedies), then refused to answer questions or allow qualified members to inspect the books (an audit that was actually specified as a member right in the bylaws). They did this for weeks, leading to the court filing to open the books, and then they fought that suit for another eight months. During this time their message was "trust us; we know what we're doing", rather than open communication. By the time members gained access to the financial records (and found gross incompetence but not malfeasance), the damage to many relationships within the organization had been done.