A police chief got a taxi from his home in Blackpool to Manchester Arena to assume a 'key role' on the night of the bombing - and his Blackberry device ran out of power on the way, the public inquiry into the terror attack heard.
Chief Superintendent Allan Gregory, who was British Transport Police's 'silver' tactical commander, said he tried to contact a superintendent who lived 25 minutes away to send him to the scene as a 'bronze' ground commander, but 'couldn't make the call connect' and got his answerphone.
Instead, he contacted Superintendent Kyle Gordon, who was off-duty and not on call, at 11.12pm.
Chief Supt Gregory said he 'didn't get anything back' from him to say 'this is not going to be possible'.
The inquiry heard Supt Gordon arrived at the Arena by taxi at around 1am, two-and-a-half hours after the 10.301pm explosion.
Supt Gordon sent initial emails to Chief Supt Gregory en route, but the inquiry heard Supt Gordon's Blackberry started to fail as he travelled. He didn't have a police radio either.
Giving evidence to the inquiry on Monday, Chief Supt Gregory, who was in BTP's Birmingham control room at the time, said the use of a taxi was 'highly unconventional' and accepted it was 'not acceptable'.
"I can only say that I thought that that was the most appropriate choice at the time," he said of Supt Gordon.
The inquiry heard the 'bronze' commander for Greater Manchester Police was an Inspector who was on scene within 10 minutes.
Chief Supt Gregory was asked why BTP 'needed someone of a more senior rank at the cost of arrival time'.
He said he didn't know GMP's arrangements at the time, adding: "I can only say that I thought that that was the most appropriate choice at the time.
"There may have been better candidates to undertake that more quickly. At the time it felt like the most appropriate appointment."
He accepted in hindsight there may have been 'better choices' who were nearer, but said: "The pressure and the challenge and the sheer weight of what I’d just been briefed on is something that means you are looking to get a team that you know well and that you have confidence in and trust in to get them to the scene to work."
The inquiry was told that subsequently, a chief inspector was deployed from her home to the Arena for BTP as a 'bronze' commander, and arrived far sooner than Supt Gordon.
Supt Gordon's 'ability to email later in his journey was compromised by the fact that his device ran out of power'.
A lack of communication on the night between GMP and BTP was referenced.
At the time he took command for BTP, Chief Supt Gregory said it was clear to him that GMP had 'assumed primacy' of the response.
But he said he didn't contact fire or ambulance commanders on the ground - a fact he said was a 'matter of regret' for him.
"I didn't do that," he said. "My sole focus was around Greater Manchester Police and the silver commander for that organisation.
"That's a matter of regret. I should have been more diligent around reaching out to fire service silver and the ambulance silver, and having conversations about what they understood."
Chief Supt Gregory said he was not made aware that GMP had declared Operation Plato, a pre-planned response to what the force believed was a marauding terrorist firearms attack which involved the withdrawal of personnel from hot zones.
He told the inquiry he would have expected to have been informed.
"It was clear there were a large number of BTP resources on the scene and if Plato was declared then it would mean there were consequences for those resources," he said.
And asked if he had been adequately trained for the incident, Chief Supt Gregory said: “I honestly do not think that I could ever have been adequately prepared for the challenges of that night.
"In terms of the sheer scale of events, the sheer amount of information coming at you in different order and the sheer tragedy, no."
Policing experts appointed by the inquiry have raised a series of criticisms of BTP, including that the force made 'no significant contribution' to tactical scene command, the inquiry heard.
The experts said there were also 'failed attempts' by BTP to reach GMP commanders.
Chairman of the inquiry, Sir John Saunders, said: "The difficulty that BTP had generally on the night in communicating with anyone when you're part of the rescue service...it seems to me to be crying out to be looked at."
Earlier on Monday a police chief whose role was to oversee BTP's initial response to the bombing accepted there wasn't a 'three-way communication between fire, ambulance and police' during his involvement.
Chief Inspector Tony Lodge was the 'senior duty officer' - SDO - in the initial stages and accepted he took no action to make sure the emergency services were meeting together at one location.
The inquiry heard BTP selected a car park near the Arena as a rendezvous point.
The North West Ambulance Service chose Hunt's Bank and the fire service a fire station three miles away.
The May 22, 2017, bombing claimed 22 lives.
More than 260 people were physically injured, with 160 requiring hospital treatment, after terrorist Salman Abedi detonated a shrapnel-laden bomb in the City Room foyer area of the Arena after an Ariana Grande concert.
