Cyber intervention? What should be the BB's response?????

With the recent tragedy in SC, their are now people who claim they talked/chatted with the killer/terrorist and before the church killings. Many say they felt he may take hostile action regarding his racial hate, what should they have done?

Recently a BB member hinted he may be suicidal, and the members did all they could in the comment section to reach out to him.

How far should a person go, when someone in cyberspace talks of harming themself or others? Should the board use the information on hand about a member to protect that person or others, if the threat appears legit? More importantly, is it the moral duty of the person or persons who honestly suspect something is amiss to take preventative action?