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Roger Dean (right) is given oxygen by ambulance staff after a fire engulfed a nursing home for the elderly, killing 11 people on November 18, 2011.

An Australian nurse who admitted to 11 counts of murder in a retirement home fire was trying to destroy evidence that he had stolen painkillers prescribed to the residents, prosecutors revealed Tuesday, according to reports.

Roger Dean, 37, pleaded guilty on Monday over the deaths at the Quakers Hill Nursing Home in Sydney in November 2011, Australian media reported.

According to documents released by prosecutors, Dean stole hundreds of tablets of oxycodone -- a powerful narcotic painkiller -- the night before the fire.

The Sydney Morning Herald newspaper reported that the prescription value of the tablets was around $82.

Police arrived the next evening to investigate after nursing home managers reported the theft, but they soon left for another call. Worried they would return, Dean then used a cigarette lighter to set fire to several beds in unoccupied rooms that had no CCTV cameras, the court documents reportedly say.

"He had armed himself with the means to set fire to the home," The Australian newspaper quoted the prosecution's documents as saying.

While the fire blazed, Dean helped some of the elderly residents escape and also persuaded firefighters to help him remove drug register books from the building. The books "would assist any investigation into his theft of the drugs," so he removed them, tore them up at his home and threw them in a Dumpster, the prosecution's documents say.

Prosecutors also allege that when Dean initially confessed, he claimed he had been having nightmares and had tried to end his life. "He further stated that in him doing this, it was Satan telling him to do it," the documents say.

Dean confessed after speaking to friends in his Bible study group, the court documents say.

Police reportedly found all the drugs in Dean's apartment in containers labeled "Roger's doctor prescribed medication," the Morning Herald reported.

Related:

Nurse admits to 11 murders after setting fire to Australia nursing home

A former nurse has admitted to 11 counts of murder at a retirement home in Australia, according to reports.

Roger Dean, 37, pleaded guilty over the deaths at the Quakers Hill Nursing Home in Sydney in November 2011, the Australian Broadcasting Corporation and The Sydney Morning Herald newspaper reported.

Dean stood by and watched as the fire ripped through the building, the Morning Herald said.

In the New South Wales Supreme Court on Monday, Dean looked at his feet and spoke quietly as he said guilty to each count. Relatives cried and held hands. He also admitted eight charges of recklessly causing grievous bodily harm and had previously pleaded guilty to stealing painkillers.

The TV station reported there were more than 80 residents in the home when the fire started.

Elly Valkay, whose mother Neeltje Valkay was killed, told the Australian Broadcasting Corporation that she was pleased justice would be done.

"It wasn't happiness of course, I still miss my mother very much and the rest of our family miss her greatly, especially her grandchildren," she added. "It was, I think, joy in my heart to see that my mother would say 'yes justice is going to be done and we're going to see it.'"

"I saw her six days a week," she said. "I still do the wrong left hand turn to go home and go past the nursing home. There has been upheaval in our family because we miss her so much. There has been nights of no sleep ... I still have nightmares."

William West / AFP - Getty Images

A swimmer stops short of a red algae bloom at Sydney's Clovelly Beach on Tuesday. Clovelly and Bondi beaches were closed to swimmers.

Sydney's iconic Bondi Beach and Clovelly Beach were closed to swimmers on Tuesday as a red algae bloom drifted close to shore, Agence France-Presse reports.

While the red algae, known as Noctiluca scintillans or sea sparkle, has no toxic effects, people are still advised to avoid swimming in areas with discolored water because the algae, which can be high in ammonia, can cause skin irritation. 

"It has got quite a fishy smell to it," lifeguard Bruce Hopkins told the Australian Associated Press. "It can irritate some people's skin but generally not much more than that."

William West / AFP - Getty Images

A boy walks along Sydney's Clovelly Beach on Tuesday.

William West / AFP - Getty Images

A seagull stands in a red algae bloom at Sydney's Clovelly Beach on Tuesday.

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A judge in Australia ordered a Sydney multimillionaire who met his wife when she worked at a lap dancing club to honor the $3.25 million prenuptial agreement now that they are divorcing, despite his argument that she was a gold-digger who used sex to lure him into a loveless relationship, Australia’s Daily Telegraph reported on Thursday.

The 58-year-old man, who was not named, told Family Court that he had become infatuated with the dancer, who is 14 years younger, in 1998 and that by the time they were married and signed the prenuptial agreement in 2005, he was "emotionally or pathologically dependent" on her, the report said.

The pair had lived together for a number of years before getting married, but the man complained that after marriage the quality and quantity of "intimate relations" declined steeply, which she reportedly disputed.

But Family Court judge Robert Benjamin said the man had not proved that his wife unfairly coerced him into a loveless marriage in 2005 and then out of $3.25 million of his $17 million estate, it said.

"(A) change in the nature of intimacy between parties when they marry is not an indication of fraud, coercion or unconscionable conduct. It is indicative of normal human behavior," Benjamin said, according to the Telegraph.

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