First responder describes arriving at London Bridge attack scene

The first paramedic to arrive at the scene of the London Bridge attack feared he might he under attack as gunfire rang out yards from where he was treating critically injured victims.

Gary Edwards was the first responder from London Ambulance Service, pulling up in his car just six minutes after the terrorists struck their first victims in a hired van.

The 29-year-old described finding a scene of chaos, with victims, members of the public and the police calling for him to help.

Within moments of arriving, he heard gunshots about 15m (50ft) from his location as police shot the attackers in Borough Market. Uncertain what was happening and fearing it might be hostile fire, he took cover.

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"I was greeted by large numbers of casualties, members of the public running towards me, multiple injured people on the floor, unable to walk, in different conditions," Mr Edwards said.

"Lots of police officers running towards me, asking for help. It was quite obvious that this has been some sort of terrorist attack.

"Soon after there were some gunshots heard behind me, about 10 gunshots. So I’ve had to retreat to safety behind my car and put my body armour on and reassess the scene.

"I heard three bursts of gunfire over the next few minutes. At the time I didn’t know if it was the attackers or the police. I was unsure, so I had to treat it as if it was an attacker using a gun.

"I feared for my safety and my health. I was in the middle of an attack – an active gunfight going on, and I was obviously unarmed. People were running towards me but I was unsure of their intentions so I was quite vigilant, watching their hands in case they had a weapon."

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As first responder, Mr Edwards’ job was to assess the scale of the incident and call for support, even if it meant passing those with critical injuries.

He explained: "There were 15 to 20 people maybe, but my first job is to assess. There’s no point in me losing myself to one patient and leaving potentially 19 people with no help. So I had to gain an overview of the scene."

Mr Edwards, who joined the Ambulance Service nine years ago, praised members of the public who helped him and his colleagues, and said his training had prepared him well.

"It is surprising how automatic it becomes – you just get on with the job, despite gunshots and the threat of someone running around with a knife.

"I’m glad I was there to help people – I’m trained to help people despite the danger. I’m glad I was there."

(c) Sky News 2017: First responder describes arriving at London Bridge attack scene