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, external 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".

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