today many people are getting subscribed (with NO authorization) automatically to this group: Sosteniamo SILVIO BERLUSCONI contro i FAN di massimo tartaglia. You have NO notification that you've been subscribed to this group.
Also consider the geographic position (screenshot) of the group contact.
Also consider that the group can't be signaled to facebook, because the feature looks like out of service.
It's clearly a mafia group, beware of!