“Heroes” star Hayden Panettiere’s death had no “signs of foul play,” cops said, revealing she was found by an “acquaintance.” Panettiere, 36, was found “unresponsive” at an apartment in Greenville, South Carolina, at around 1:50 p.m. Sunday. “Upon arrival, medical assistance was administered; however, the individual, later identified as Hayden Panettiere, was pronounced deceased at the scene,” a Greenville police spokesperson told NBC News. “The case is under investigation by the Greenville Police Department in conjunction with the Greenville County Coroner’s Office. “The preliminary investigation has not indicated any signs of foul play…