One of the first police officers on the scene of the London Bridge attack says he was met by pandemonium, as people fled in panic and the wounded lay on sidewalks.

But he also described how, within minutes, police had killed the attackers, ushered bystanders to safety and begun treating and evacuating the wounded.

Inspector Jim Cole, who was scrambled from his south London police station, said the response was “like something out of a Battle of Britain film” as officers piled into vehicles and raced to the scene.

In an account of the June 3 attack released by the Metropolitan Police, Cole said he arrived at Borough Market to find “casualties on the pavements.”

“I asked my officers to form a cordon to stop the public from going into the market, and that's when the shooting started just behind us,” he said.

“We had no idea what was going on. We didn't know if it was us shooting or if that bad guys had guns.”

Armed officers fired almost 50 rounds, killing three attackers who had plowed a rented van into pedestrians on the bridge, killing three, then jumped out and stabbed Saturday night revelers in Borough Market, an area packed with bars and restaurants. Five people died of stab wounds, and almost 50 people were wounded in the attack.

Cole said he set up a triage area inside a pub to treat the wounded, including a man who had been stabbed in the stomach.

“I then heard more shouting and a stream of people came out of the market screaming and panicking. I got them into the pub's basement as a place of hard cover,” he said.

He said that on his police radio “I could hear officers on London Bridge desperately calling for ambulances,” and got a police cruiser to take the man who had been stabbed in the stomach to a hospital.All of the 48 wounded people who were taken to hospitals survived.

Cole said that soon the situation “began to stabilize,” with the attackers dead and the immediate threat contained.

“I felt that it had only been a few moments, but it had actually been about 10 or 15 minutes,” he said.

Cole said that when he told the 200 people sheltering in the pub's basement that they were safe and would soon be evacuated, “I got a big round of applause.” “That was a really nice, unexpected moment,” he said.

Cole, 41, said the attack was “the most challenging, most intense situation I've dealt with” in an 18-year police career.

“I've dealt with a lot of death and I've been to some pretty horrific scenes in my career, but nothing has ever been on that scale,” he said. “It's going to stick with me for a long time.”

Police are questioning seven suspects over suspected links to the attackers, Pakistani-born British citizen Khuram Butt, Moroccan Rachid Redouane, and Youssef Zaghba, an Italian national of Moroccan descent.