She plotted the brutal 1997 murder of husband, Douglas, with boyfriend

The execution of the only woman on Georgia's death row , Kelly Gissendaner (pictured), was delayed because the lethal injection was 'cloudy'

The execution of the only woman on Georgia's death row has been postponed at the last minute for the second time in less than a week - because the drug used in the lethal injection she was scheduled to receive was 'cloudy'.

Kelly Renee Gissendaner, 46, was due to be given an injection of pentobarbital at a Jackson prison at 7pm on Monday in retribution for plotting the murder of her husband in 1997.

But after officials observed the drug had a 'cloudy' appearance, they postponed her death until a future, unspecified date 'out of caution', according to reports.

Earlier on Monday, Gissendaner had feasted on a massive last meal of two Burger King Whoppers, two large portions of fries, cornbread, a fatty salad, popcorn and cherry-vanilla ice cream.

It is the second time Gissendaner has been spared death from lethal injection.

On February 25, officials postponed her execution as a winter storm was due to hit the area.

It was unclear whether she received her whopping, 3.400-calorie last meal at that time.

Monday's decision came as the U.S. Supreme Court considered whether or not to grant Gissendaner a stay of execution after a last-ditch appeal for clemency was denied by state officials.

On Monday night, a Department of Corrections spokesman told the Gwinnett Daily Post: 'Prior to the execution the drugs were sent to an independent lab for testing of potency.

'The drugs fell within the acceptable testing limits. Within the hours leading up to the scheduled execution, the execution team performed the necessary checks. At that time, the drugs appeared cloudy.

'The Department of Corrections immediately consulted with a pharmacist, and in an abundance of caution, inmate Gissendaner’s execution has been postponed.'

More than 100 protesters were gathered outside the prison where Gissendaner was to be executed, pleading with officials to spare the mother-of-three's life.

Riot police were also reportedly stationed outside the facility.

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More than 100 protesters surrounded the Jackson-based facility where Gissendaner was due to be executed, pleading with officials to spare the mother-of-three's life. Riot police are also outside the prison

'Kelly is loved': Death penalty opponents gathered on the steps of Georgia's State Capitol in Atlanta on Monday evening

Praying: Michael Patter, senior minister at Central Congregational United Church of Christ, prays silently during a vigil for Gissendaner, who made headlines across the world with her 3,400-calorie last meal request

Murder: Gissendaner (pictured, left, in her arrest mugshot from 1997) is due to be executed for plotting the murder of her husband, Douglas. However, her boyfriend Gregory Owen (right) who carried out the deed, will be eligible for parole in eight years after accepting a life sentence and testifying against Gissendaner in trial

Gissendaner, who made headlines globally with her 3,400-calorie last meal request, would have become the first female to be executed in Georgia in 70 years if the injection had gone ahead.

Her attorneys had recently launched a final attempt to persuade the state's Board of Pardons and Paroles to commute her death sentence to life without parole.

They were backed by a petition, which had gained over 70,000 signatures by Monday evening, saying Gissendaner has turned her life around, even earning a theology degree behind bars.

Nearly 400 clergy members, who signed the petition, had highlighted Gissendaner's acceptance of 'full responsibility' for her crime, as well as her graduation from the program for incarcerated women at the Candler School of Theology at Emory University, through which she became a teacher.

However, on Monday afternoon, the board announced it was standing by its February 25 decision to deny clemency to Gissendaner, whose last meal included a salad drenched in buttermilk dressing.

It said it had voted to abide by its earlier decision after 'careful consideration' of her case. The Supreme Court was still deciding whether to grant a stay of execution on Monday night.

Gissendaner had been denied clemency at a hearing last week, but her lawyers had argued that extra witnesses from within the prison system could help persuade the board to change their minds.

Previous attempts have rested on the inmate's remorse and new-found faith. In a statement ten years ago, Gissendaner herself said: 'I deserve to be here, but I don't deserve to die.'

She has also drawn attention to the fact that, while she did not kill her husband, the man who struck the fatal blows is not facing the death penalty - and will, in fact, be eligible for parole in eight years.

Indeed, although her boyfriend, Gregory Owen, stabbed her husband, Douglas, at her urging, he could be freed in just eight years after accepting a life sentence and testifying against her.

Gissendaner's death via lethal injection was previously scheduled to take place last week. However, it was canceled after a 'rare' storm caused disruption in the area, closing schools and businesses.

Monster meal: Gissendaner (pictured, above, eating a regular prison meal) requested an enormous spread for her last meal, including two cheeseburger meals, two large orders of fries, cornbread, popcorn and ice cream

Locked away: Gissendaner (pictured in 2004) has been locked up for the past 17 years after her conviction

If executed, she would have become the first woman executed in Georgia since 1945 and only the 16th put to death nationwide since the Supreme Court allowed the death penalty to resume in 1976.

In their motion, Gissendaner's lawyers noted that the parole board had already heard from many people testifying about her faith and remorse at a hearing last week before denying her clemency.

But, her lawyers argued, the board did not hear from many Department of Corrections employees whose perspective 'would have left no doubt that a grant of clemency is supported in this case.'

I deserve to be here, but I don't deserve to die. Death row prisoner Kelly Gissendaner

The most important witness the board did not hear from is Kathy Seabolt, who served as her warden for six years, first at Metro State Prison and then at Lee Arrendale State Prison.

Seabolt could testify that former parole board chair James Donald promised Gissendaner would receive clemency, her lawyers wrote.

Each time the topic came up in conversations between Donald and Seabolt, 'Donald reiterated his statement that Ms. Gissendaner did not need to worry about clemency as it was a foregone conclusion,' they wrote.

Gissendaner's lawyers also urged the parole board to subpoena some other corrections employees so they can testify without fear of retaliation.

Although department rules allow employees to speak to lawyers for capital clemency proceedings, the reality is less clear, Gissendaner's lawyers wrote.

Some employees had said they would testify and provide written statements on her behalf, but changed their minds after getting a memo from the new warden, who succeeded Seabolt last year.

Petition: Gissendaner's attorneys were backed by a petition , which had gained more than 70,000 signatures by this evening, saying Gissendaner has turned her life around, even earning a theology degree behind bars

'Under no circumstances are you to discuss this with people outside the institution. Staff should also be careful what is said to other inmates and personal feelings are to be suppressed,' Kathleen Kennedy wrote on January 29 as she notified staff of the likelihood of the upcoming execution.

Gissendaner's lawyers also urged the board to consider that before trial, she had been offered the same plea deal as Owen - life in prison with an agreement not to seek parole for 25 years.

'At one time, therefore, all the parties involved in the case thought a sentence less than death was appropriate for Ms. Gissendaner,' her lawyers wrote.

Kelly is a living testament to the possibility of change and the power of hope. She is an extraordinary example of the rehabilitation the corrections system aims to produce. Petition

Owen, who is the one who stabbed Douglas Gissendaner to death, took the deal and testified for the prosecution. Gissendaner balked at the parole agreement and took her lawyer's advice to go to trial.

The parole board has granted clemency before in cases involving disproportionate sentences for co-defendants, her lawyers wrote.

'In fact, this Board has on at least four occasions in the past commuted a death sentence of a co-defendant who was not the actual killer of the victim,' the lawyers wrote.

Douglas Gissendaner's parents and sisters wanted her to be executed, but two of Kelly and Douglas' three children asked the parole board to spare her life, the lawyers wrote.

In statements submitted with their mother's clemency application, Kayla and Dakota Gissendaner described a journey from bitterness and anger to forgiveness.

'We also believe that Kelly's death will not restore them or make them whole,' Gissendaner's lawyers wrote of the entire Gissendaner family.

Saying a prayer: On Monday evening, a Twitter user named Rachel wrote: 'Praying for #KellyGissendaner, may she find the love and mercy our broken systems could not find for her. #kellyonmymind'

Angry: User Kir Alexandra questioned reports of police in riot gear being dispatched to the prison in Jackson

The petition for Gissendaner's clemency, which was launched by Jeania Ree Moore, described the inmate as a 'powerful voice for good' who has 'lived a life of purpose' since her incarceration.

'While incarcerated, she has been a pastoral presence to many, teaching, preaching and living a life of purpose," the document stated.

'Kelly is a living testament to the possibility of change and the power of hope. She is an extraordinary example of the rehabilitation that the corrections system aims to produce.'

It urged members of the public: 'Do not let this travesty of justice happen on your watch.'