A simple pencil yesterday came within inches of bringing undone the most complex, wide-ranging and expensive murder investigation in Australia’s history.

Authorities at all levels were last night asking — and being asked — how WA’s most guarded and scrutinised prisoner, accused Claremont serial killer Bradley Robert Edwards, could end up injured and bleeding in a jail shower block at Hakea Prison.

Last night, Mr Edwards had been moved to Casuarina Prison on a strict “protective regime”, while the investigation continued into how his injuries occurred.

Confusion reigned earlier in the day after Corrective Services Minister Fran Logan said Mr Edwards had been attacked by another prisoner, only to retract the revelation within hours.

And the families of the alleged murder victims — Sarah Spiers, Jane Rimmer and Ciara Glennon — were again left waiting to see if Mr Edwards would even be fit enough to attend court this morning. “I would like him to stand trial for the alleged crimes,” Jane Rimmer’s sister Lee said.

About 7.55am yesterday, Mr Edwards, 50, was showering in the secure unit of the maximum security Hakea Prison ahead of a scheduled trip to the Supreme Court when he was found by a prison guard injured, bleeding and disoriented.

He could not — or would not — tell prison officers what had happened to him, but a pencil found on the floor nearby told some of the story.

After being treated on-site, Mr Edwards was taken by ambulance to Fiona Stanley Hospital under armed guard.

He was seen being wheeled into the emergency department with a bandaged right ear and an apparent scratch on his neck.

Even as the packed courtroom in Perth was being told Mr Edwards had suffered a “health issue” and would not be appearing, State Government ministers were being briefed and a police investigation was swinging into action.

Hakea’s Unit 6, which houses protected prisoners, was immediately locked down — with 21 prisoners inside at the time under suspicion.

But the possibility of Mr Edwards having tried to harm himself was also not being ruled out, despite Mr Logan clearly stating it had been an attack.

“At this stage they believe it was an attack by another prisoner, it occurred in the shower and it occurred about 20 minutes after the prisoners were unlocked,” Mr Logan said.

“Unfortunately, prisons are full of people who are quite violent and some are quite disturbed and it is not unusual for prisoners to goad each other and sometimes attack each other.

“Obviously everything is done to try and stop that from occurring. Sometimes in a situation which is in an area which is private, such as a shower, these things do occur and in this case it did.” Minutes after Mr Logan’s press conference, Corrective Services Commissioner Tony Hassall would not confirm that an assault had taken place.

And so Mr Logan was forced into an embarrassing retraction, instead saying: “There is no indication about how the injury has occurred.”

However, given Mr Edward’s injuries — which were never considered life-threatening — did happen, there were still grave concerns about how one of WA’s most keenly watched prisoners could come so close to serious harm.

“I am concerned,” Attorney-General John Quigley said.

“We want to keep this accused in good health to face justice without delay.

“I don’t want him going off to hospital and then saying the trial has got to be delayed or nonsense like that. We want to keep this prisoner fit and in good health to face his day in court.

“This community has waited for over 20 years for the commencement of the trial and I would be very concerned if there was anything that happened to him in prison that caused any delay.” Mr Hassall said there were no CCTV cameras in the shower block where Mr Edwards was found.

“It is a protection unit, a secure part of the prison where we put prisoners who we deem need protection or ask for protection,” he said.

“And the unit was normally staffed with one senior officer and nine prison officers.

“The unit was unlocked as normal at 7.30am, there was no indication there was any issues ... he obviously went for a shower and that’s when the officer found him about 15 to 20 minutes later.”

Mr Hassall said he had sent senior staff to Fiona Stanley Hospital and Hakea Prison to help in the investigation.

A spokesman for Mr Logan said Mr Edwards would be “intensely supervised” at Casuarina while his future needs inside prison were assessed. The court hearing delayed by Mr Edwards’ injuries is scheduled to resume at 10am.