Prison medical staff tried to revive him until ambulance officers arrived, however he died at the scene. Carl Williams An autopsy will be conducted to see if Williams died as a direct result of the attack or due to a heart attack. There are conflicting reports from police and Corrections officials over where the deadly attack took place. Williams was attacked by two prisoners while in a shared common room.

However, deputy corrections commissioner Rod Wise told a separate media conference that the men shared an exercise yard and a day room in the Acacia complex. When asked where the attack took place, he said it did not occur in the exercise yard. Mr Wise said the attack was captured on security footage. Two inmates are being questioned by homicide squad detectives. A prison officer was about 10 metres away when the incident occurred, corrections officials said.

Mr Wise said Williams was housed in a unit with two other inmates who have been placed in a secure area. The three men were allowed to associate with each other for six hours a day, between 8am and 2pm, but were not always supervised. ‘‘There are times when they are supervised, there are times when they are not,’’ Mr Wise said. When asked why Victoria’s highest-profile inmate was not under constant guard, he said it was "impractical" to provide that level of protection. He said there was no history of conflict between Williams and the two other prisoners who shared his unit.

Mr Wise said it was "a concern" that a prisoner could be bashed to death while in the state’s highest security facility, "but no prison environment is without risk". Mr Wise said Williams was "regularly supervised by staff" but there was no permanent staffing complement in the unit. Prison staff found Williams after the bashing, he said. Sir Ken Jones would not elaborate whether any other prisoners or prison guards were present or whether there was video footage of the incident. He said a ''blunt implement'' used in the attack.

When asked whether Williams’s death would affect any ongoing investigations, Sir Ken said while there were a number of suppression orders in place: “I'm not going to rule anything in or out but it doesn’t take a genius to work out there will be an impact and as a result of that I’ve got people working on that.” “Obviously, in view of the history of Carl Williams, we are developing a number of investigations. Sir Ken said questions whether Carl Williams was adequately supervised at the Acacia unit should be left to Corrections Victoria. Asked whether he was disappointed at the prison management of Williams, he said it was too early to criticise any agencies. “We will be looking at any and all complications”.

Asked whether he believed Williams’s death had anything to do with a newspaper report today that Victoria Police had paid his daughter’s school fees, he said: “It’s too early to say”. He said that at this stage police are not aware of any threats for the safety of Williams’ family but “we are looking at all possible ramifications”. Police Minister Bob Cameron said the violent death would be investigated by Victorian Police, the State Coroner and the Office of Correctional Services Review in three separate inquiries. "I have had a conversation with the chief commissioner this afternoon and he assured me that no stone will be left unturned to get to the bottom of this murder," Mr Cameron said. "Simon Overland and police got to the bottom of the gangland wars and they will get to the bottom of this," he said.

Carl Williams was sentenced to life with a minimum of 35 years in 2007 over four murders during Melbourne's long-running gangland war. Detectives will investigate whether the attack was sparked by reports today that police had paid Williams’ daughter's school fees. Two plainclothes police arrived at the home of Williams’ father, George, in Broadmeadows about 3.10pm. The men, believed to be homicide squad detectives, were let into the property by an unknown man. A friend of George Williams asked a reporter who knocked on the door to leave him alone.

Mourners gathered outside the house abused waiting journalists - one flashed his buttocks and said the media was responsible for Williams’ death. One screamed at reporters, accusing the media pack of being ‘‘animals’’. A family friend who said he had known George Williams for 20 years, told waiting media, those gathering at the Williams home ‘‘still don’t know what’s going on’’. ‘‘No one knows. We have not heard anything. I heard it on the news. He had a massive heart attack, that’s what I heard,’’ the man said. ‘‘Now we are getting conflicting [reports]. [George] has not been told anything yet [by prison officials]. They have not come out to see him.

The friend said detectives who arrived at the house this afternoon ‘‘just came out to tell him ‘you have got counselling if you need it’, and all this’’. ‘‘We don’t know how Carl died or how it happened. No one knows anything.’’ Asked if George Williams was angry, the man said: ‘‘You work it out. It’s [Acacia unit] supposed to be maximum security, isn’t it.’’ ‘‘[George] will talk to you when he’s ready.’’ When The Age phoned Williams' ex-wife Roberta this afternoon, an unidentified man who answered the call said “f--- off, you goose” before hanging up.

All the shutters at Roberta Williams’ Essendon house were closed and no one answered the door. The Age’s Andrew Rule, co-author of the Underbelly books on which the popular TV series was based, said Williams’ killing was ‘‘another episode in a very violent life’’. ‘‘He was lucky not to be killed 10 years ago by the Moran brothers, who are now both dead themselves,’’ he told Radio 3AW. On the question of who killed Williams and how they got the chance, Rule said there is ‘‘a constant threat of opportunism that runs through the minds of violent men in jail’’. Shortly after the news broke this afternoon, underworld figure Mick Gatto said he had heard rumours about Williams' death but that was all he had heard.

‘‘I would rather let dead dogs lie,’’ he said. ‘‘If you hear any more let me know but I would rather not comment on him.’’ He said Williams was ‘‘certainly not’’ a friend. Williams, who gained notoriety for his role in Melbourne’s gangland war, had been on a modified diet and had lost weight since he was sentenced to a minimum of 35 years in 2007 over four murders. He had one daughter, with former wife Roberta Williams.

In 2007, he pleaded guilty to murdering Jason Moran in June 2000, Lewis Moran in March 2004 and Mark Mallia in August 2003 and conspiracy to murder Mario Condello in May-June 2004. He had previously been found guilty of the murder of Michael Marshall, killed in October 2003. Williams was denied permission to attend the funeral of his mother, Barbara, at the end of 2008 after he was deemed too much of a flight risk. Loading His father George was released from Barwon Prison in June last year after serving 20 months for drug trafficking.

with Adrian Lowe, Robyn Grace, Reid Sexton and AAP