Emergency call records have revealed the confusion that developed among prison staff and emergency call handlers after the execution of convicted murderer Christa Pike went wrong last month in Tennessee.

Pike, 50, who killed Colleen Slemmer alongside her then-boyfriend in 1995, was given two doses of lethal injection on 30 September. Once it became clear that she was not going to die from the dosage, she was taken to hospital.

The confusion resulted in part from an apparent disconnect between prison staff, according to the AP news agency, which first obtained audio of the emergency calls.

This allegedly delayed Pike's treatment. The BBC has asked the state corrections department for comment.

The department has not yet stated what it thinks went wrong in the attempted execution of Pike. Pike's legal team has offered the explanation that the pentobarbital chemical, with which she was injected, probably spread under skin rather than reaching her bloodstream in a sufficient quantity to kill her.

Pike has now been discharged from hospital, though in their most recent update on her health, her team cautioned that she faced a "long road to recovery". It is not clear what treatment, if any, she is receiving now that she is back in prison.

Her case is now in uncharted territory as she is thought to be the only person to have survived an execution attempt by lethal injection.

Slemmer's mother, who was among those pushing for Pike to be put to death, has branded the failed execution a "mess".

Pike's boyfriend at the time of the murder, Tadaryl Shipp, remains in prison, having been spared the death penalty because he was not yet an adult when the crime was committed.

The sequence of events on the evening of 30 September was pieced together by US media using a combination of emergency call recordings and transcripts. The records were published in full by the Nashville Banner news outlet.

The initial call made from Riverbend Prison - which was reportedly made at 20:40 local time - was considered to have been false by first responders, after the caller was unable to verify themselves using a code.

That person seems to have been in a part of the prison where the injections were taking place. They said: "We've been carrying out an execution tonight. We've administered 10 grams of pentobarbital. The person is not yet deceased. That started approximately one hour ago. And we're calling for an ambulance." The Nashville Department of Emergency Communications released records of its conversations with other local agencies as it tried to confirm whether the call was genuine.

The confusion appears to have been compounded by other prison staff, from the institution's central command, who said at 21:07 that they "would have been the ones to call in" and that they "did not make that call".

It was not until about 21:11 that prison officials verified that the initial call, made about half an hour previously, had in fact been genuine. At that point, the emergency responders were allowed through the prison gates.

A later call acknowledged that the situation had been chaotic. At 21:34, as Pike was being taken to hospital, one medic asked a colleague to ensure the prison knew where Pike was being taken, "just 'cause there's been so much other confusion". Pike's lawyers are yet to comment on the recordings.

Over the course of last week, her team provided frequent updates on Pike's condition - detailing how she had regained her ability to walk and talk before ultimately being discharged from hospital care.

It is unclear whether or when the state will try again to execute Pike. Some state Republicans have called for a new method to be attempted. Pike's legal team, meanwhile, are calling on Tennessee Governor Bill Lee to commute her punishment to the lesser sentence of life in prison without parole.

For now, Lee has paused the state's executions for the remainder of the year. An investigation is taking place into what went wrong with Pike's execution. The head of the state's corrections department is resigning from his post in the wake of the botched execution.