London, October 8 : Anna Nicole Smith faced interrogation over an alleged plot to murder her stepson.

The late Playboy Playmate tied the knot with late multi-millionaire oil tycoon Howard Marshall II in 1994 at the age of 26.

The model alleged she had been given a verbal promise from her husband that she would be entitled to half of his estimated 366-pound million fortune, reports the Daily Express.

After Howard’s natural death in 1995, his son E. Pierce Marshall turned to court, claiming he was the sole heir of the entire property as per the various wills and trusts of his father.

And now newly acquired FBI documents have revealed that the actress was under investigation between 2000 and 2001 over a purported plot to rope in a hitman to kill Pierce Marshall.

The investigation was subsequently dropped over lack of evidence against the star.

Pierce Marshall died of an infection in 2006, aged 67. A year later Smith died at a hotel in Florida. (ANI)