An undercover firearms officer has spoken of the moment he was confronted with a masked gunman in a raid on a New Romney building society.

The officer, known only as Echo 19 to protect his identity, told a hearing at Folkestone magistrates court that within eight seconds he had confronted Challock resident Robert Haines and then shot him three times.

The father-of-three was fleeing Nationwide in the High Street to his escape car down an alleyway with £105,000 in one hand and a sawn-off shotgun in the other.

Taking cover behind a wall Echo 19 stooped and ran alongside before getting his first glimpse of Haines.

He said: "The first thing I noticed was the dark clothing but the most memorable thing for me what the face.

"It was covered almost entirely in black but the eye holes were cut out and I could clearly see the white flesh. It was that contrast that I immediately thought robber; it was so distinctive."

Haines appeared to flinch and quickly headed towards the waiting silver Mercedes in the car park near Church Road.

He said: "With the most amazing speed he's turned to his left and let the gun down and he's turned and faced me and I thought the speed of which was amazing. Within a second he'd fired.

"I saw the flash from his left hip and I heard a loud bang and I thought; I'm being shot at. He's trying to kill me or he's trying to kill my friends. He was trying to kill us. I'm sorry; it's as simple as that.

"I raised my weapon up and I fired two shots. He was still facing me when I'd fired the shots and he remained facing me. I thought, have I missed or is he wearing body armour because in my mind he was still an imminent threat. I had to remove this threat.

"I didn't know if my colleagues were hit and I didn't know if I'd been hit and it was vital that I stop him from shooting again so I fired a third shot. I then noticed he slumped and fell to the ground."

Echo 19 shouted "get your hands up, let me see your hands". Haines, face down with his arms underneath his body, did not move.

He continued: "I took that as him being incompliant. All I thought at that stage was that he's gearing himself up for another attack. I knew there was a gun, there was no response, he was still a threat, and so I needed to use another form of force. I approached his left hand side and I kicked him as hard as I could in his ribs and I shouted show me your hands."

Echo 19 said he could not remember Haines moving but next remembered a taser being fired into the 41-year-old.

Haines' shotgun was later found to be 15 metres away from his body.

Police medics moved in to assess Haines' injuries before he was transferred to William Harvey Hospital by ambulance. He was pronounced dead an hour later at 9pm.

The only injury Echo 19 sustained, along with several other officers, was a graze on his head caused by low doors.