Is Man On Fire based on a true story

I’ve always assumed it was based on the director’s commentary. In it, Scott goes on in detail explaining how he based the actions in the movie on the real events. Text onscreen also point to it being based on reality. Now I’m reading about the author and how it is a complete work of fiction?

The Internet is not much help as there is a lot of sites that claim it is true/not true. Does anyone have the straight dope?

The author claimed to have based the novel on 'an actual [Mafia kidnapping] event in Italy in ‘75’ (cite).

He researched the novel using lawyers, anti-Mafia investigators and Mafiosi, who were introduced to him by an Italian he’d assisted following a heart attack (cite).

I don’t know about ‘complete,’ but even if it is based on a true story, it’s still a work of fiction. That doesn’t rule out that some of the events might have had their basis in fact.

Moving this thread from General Questions to Cafe Society, where it will catch the attention of more movie buffs…