Michael Madsen, a frequent Quentin Tarantino collaborator on films like "Reservoir Dogs" and a veteran actor in "Free Willy" and more, has died at 67.

Michael Madsen apparently went into cardiac arrest and was found unresponsive in his home in Malibu, California, on Thursday morning, according to his manager.

Actor Michael Madsen, known for his roles in "Reservoir Dogs" and "Kill Bill," has died at the age of 67. Madsen's death was confirmed Thursday by his publicist, Liz Rodriguez. Madsen was found unresponsive Thursday morning at his home in Malibu, California, and is believed to have died due to cardiac arrest, Rodriguez told ABC News.