Actress Mary Mara, known for star turns in “ER” and “Criminal Minds,” has apparently drowned while swimming in the St. Lawrence River at Cape Vincent, New York, authorities said. Mara, who was 61, was visiting her sister Martha’s summer home when the “apparent swimming accident” occurred, the actress’ brother-in-law, Scott Dailey, told People. “The preliminary investigation suggests the victim drowned while swimming,” New York State Police said in a statement. “The victim’s body showed no signs of foul play and was transported to the Jefferson County Medical Examiner’s Office pending an autops…