How Frank Sheeran killed Jimmy Hoffa: The shocking claims made 41 years after the legendary union activist vanished

• Labor union leader Jimmy Hoffa mysteriously disappeared on July 30, 1975
• Frank Sheeran was looking for absolution before his death in 2003
• He told former lawyer Charles Brandt how he killed his close friend Hoffa in a detailed account chronicled in the book, I Heard You Paint Houses 
• Sheeran said he tried to subtly hint to Hoffa that something was amiss by taking his usual place in the passenger seat of the car
• They drove to empty house for supposed mafia meeting, but Sheeran said he shot Hoffa in the back of the head from point blank range
• FOX anchor Eric Shawn helped launch 2004 investigation of the house where Sheeran claimed the murder took place
• Blood traces matched Sheeran's account of where Hoffa's head hit the floor before he was dragged and stuffed in body bag in kitchen 

Mafia killer Frank Sheeran said he tried to alert union activist Jimmy Hoffa that something was wrong before he fired two shots into the back of his dear friend's head.

Hoffa's legendary disappearance 41 years ago has remained an unsolved mystery, but for FOX News anchor Eric Shawn, who played a significant role in launching a 2004 investigation, the evidence is clear.

Following Sheeran's instructions to the Michigan home where he said he killed Hoffa, Shawn, along with fellow Fox News producer Ed Barnes hired a forensics team to dig up the floor boards.

What they found were decades-old blood patterns that matched Sheeran's own account, which he finally disclosed in an attempt to seek absolution before his death in 2003 at the age of 83.

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Hoffa was a working-class icon who turned the International Brotherhood of Teamsters labor union into a nationwide movement before falling from grace and going to jail for racketeering.

He was pardoned by President Richard Nixon and was making his comeback when he was summoned to a meeting with two mafia dons on July 30, 1975.

His abandoned car was found outside the Detroit restaurant and no trace of him has been found since.

Countless theories have prevailed over the years, but Charlie Brandt, Sheeran's former lawyer-turned-writer has had the privilege of telling Sheeran's story.

In the book, I Hear You Paint Houses: Frank 'The Irishman' Sheeran And Closing The Case On Jimmy Hoffa, Brandt recounted the fateful car ride before Hoffa's death. 

Sheeran, along with two others, picked Hoffa up at a restaurant, saying they were headed to a mob meeting.

In the book, Sheeran said he purposefully took Hoffa's usual place in the passenger seat as a subtle warning to his friend that things were amiss. 

According to Shawn, the FBI found a single hair that matched Hoffa and corroborated Sheeran's account. 

But Hoffa failed to take notice, and Sheeran knew he was stuck between a rock and a hard place given the orders from mob bosses to kill his dear friend.

When they arrived at the empty house, Sheeran said he lingered behind Hoffa and shot him twice in the head from point blank range.

Brandt explained: 'Hoffa was Sheeran's friend but you didn't defy orders. If he hadn't killed him he'd have been shot himself. He said the mafia was upset because Hoffa hadn't shown enough gratitude over Dallas.

'I realized he was talking about the assassination of President Kennedy in 1963. It was always rumoured that the killer, Lee Harvey Oswald, wasn't working alone and that the mob was behind it. 

'So I asked Sheeran and his face turned to stone, he raised his right hand at me and just brushed me off, saying "I'm not going anywhere near Dallas".

'I was sure he had something to do with it and kept asking. It was a classic mob hit - Oswald thought he would get away, but Jack Ruby then killed him.

'Eventually Sheeran admitted to taking three rifles to Baltimore - he understood these had then gone to Dallas. I didn't get anything more juicy than that...' 

Hoffa's son James P Hoffa also told Shawn that his father would have been wary of getting into a car with the other suspects listed by the FBI - but he would have trusted Sheeran. 

Brandt said Sheeran gave him the directions to the house where he said he killed Hoffa, and a forensic team sprayed luminol on the floors in 2004 to detect traces of blood..

Nearly three decades after Hoffa disappeared, the test revealed blood on the main entrance, foyer, and hallway leading to the rear kitchen.

The blood patterns matched Sheran's account of where Hoffa's head would have hit the floor before he was dragged to the kitchen and wrapped in a body bag, Shawn claimed.

According to Sheeran, Hoffa was later cremated at a funeral home with mob connections.  

Sheeran's daughter Dolores Miller said: 'He was among the top suspects and the FBI put him in prison time and again, hoping he'd crack. But he never did.

'Then towards the end of his life he told me he wanted absolution. I remember saying he had to be truly sorry for the things he'd done in the past, that if he had his time again he wouldn't do the things he'd done.

'He said he was sorry and I drove him to the church to confess. He seemed much happier after that.'

In the final five years of his life, Sheeran poured his heart out to writer Charles Brandt. He died in 2003, six weeks after reading the finished manuscript, and did not tell family what he'd done.

'We never discussed it before he died and Charles didn't tell me the truth until the book came out,' Miller said. 

Brandt's book will be adapted to the silver screen, starring Robert De Niro as Sheeran in a collaboration with Martin Scorsese.

The film has been in the works for several years, but filming is reportedly due to begin in January 2017 after the rights were purchased at this year's Cannes Film Festival in May.