Law enforcement agencies here in Connecticut, and also in Rhode Island and Massachusetts are urging caution as speculation continues to grow over a potential serial killer following the discovery of at least seven sets of human remains in recent weeks. Investigators say there’s no current evidence linking the deaths, but some experts believe the pattern warrants deeper review. Former prosecutors and police officials say the remains could be unrelated, accidental, or natural deaths. But social media chatter is exploding. For now, officials say there’s no known threat to the public.