After suffering a stroke earlier, his family took the difficult decision at this time, to remove his life support and he passed away at the age of 51.
Source Wikipedia:
John Daniel Singleton was an American film director, screenwriter, and producer best known for directing Boyz n the Hood, for which he was nominated for the Academy Award for Best Director, becoming, at age 24, the first African American and youngest person to have ever been nominated for that award.
