At least two Americans are mourning the death of Venezuelan leader Hugo Chávez. Actor Sean Penn and filmmaker Oliver Stone released statements expressing grief after the long-time president passed away Tuesday afternoon. "Today the people of the United States lost a friend it never knew it had. And poor people around the world lost a champion," Penn said in a statement to The Hollywood Reporter. "I lost a friend I was blessed to have. My thoughts are with the family of President Chavez and the people of Venezuela." Stone called Chavez " a great hero," and said he would "live forever in history."