Strange as this sounds, TMZ is reporting that “sources intimately connected with the Heath Ledger investigation” are saying “it’s possible the actor died of natural causes due to alleged findings that the toxic drug levels in Ledger’s system was “low enough that it may not have caused his death.” TMZ’s sources are saying that Ledger’s heart simply “stopped…it could have been a heart attack but it’s not certain, at least not yet.” The report acknowledges the bizarreness of a non-obese 28-year-old dying of natural causes, but says “it happens.”