SLAIN gangland killer Carl Williams was beaten so badly paramedics trying to save him were unable to recognise one of Victoria's best-known faces.

A jail source told the Herald Sun yesterday that prison authorities hadn't told the five ambulance officers who their stricken patient was.

"Carl was beaten to such a pulp that he was unrecognisable. The ambos never even knew who it was they were treating," the source said.

The Herald Sun has discovered Williams was attacked at 12.48pm on Monday, and jail authorities didn't call Ambulance Victoria until 1.21pm.

Williams, 39, who had been dragged from the attack scene in a common shared room and put in his cell, was still alive during that 33-minute gap.

It was at least 25 minutes before the first prison officer found the bashed and bleeding Williams in his cell, after the alert was raised by other inmates.

The prison source said a "Code Black" - jail code for a serious medical alert - was declared immediately. Four prison medical officers lifted Williams out of his tiny cell and back out into the shared area where he was attacked, so they would have more room to work on him.

"But Carl wasn't revivable. He had massive head injuries and substantial blood loss," the prison source said.

"There was a lot of blood spatter around the kitchen table where Carl was sitting when he was first attacked from behind."

The first of three ambulance crews arrived at 1.32pm; he was declared dead at 1.47pm.

Williams's father, George, 63, is in increasingly poor health and sources said yesterday he might not make it to his son's funeral, likely to be held on Thursday or Friday at St Therese's Catholic Church, Essendon.

A 2007 court hearing was told George Williams suffered chronic heart disease, diabetes, anxiety and depression. His family expressed concern then that he would not survive a 20-month jail term for drug trafficking.

Carl's ex-wife, Roberta Williams, is making funeral arrangements; but there are also worries there could be friction.

It is not known whether any of Carl Williams's many former girlfriends will attend. Their appearances in other forums, such as court hearings, prompted heated exchanges when Roberta was confronted by them.

Those close to the slain underworld multiple killer and drug boss say they don't want his funeral to turn into a circus, and are also concerned would-be gangsters will turn up in droves.

Williams's arch enemies - the Moran family - have not commented on his bashing death.

A friend of Judy Moran said she was not prepared to comment on the gangland matriarch's behalf.

The friend said Mrs Moran, on remand on a murder charge, had a bail application next week and did not want to say anything that could affect its outcome.