Cornered killer Raoul Moat told the first officer to confront him: "Shoot me, f****** shoot me" while holding a sawn-off shotgun to his head, the inquest heard.
The officer said the maniac expressed his hatred of police but ended up apologising when he realised the firearms expert was from West Yorkshire and not the Northumbria force he detested.
Moat shot himself after police fired two experimental Taser rounds at him following a six-hour stand-off in Rothbury, Northumberland, in July last year. He was wanted for blasting ex-lover Samantha Stobbart, killing her new boyfriend Chris Brown and blinding Pc David Rathband, 24 hours later.
The officer, who gave evidence anonymously behind a screen, said he stood just 10 metres (32ft) away from Moat, without a ballistics shield, knowing Moat had declared war on police.
The inquest at Newcastle Crown Court heard that the armed officer and his colleague raced to the scene after another officer in a car gestured for them to follow from Rothbury centre.
They arrived at the riverside to see a man in a baseball cap facing away from them, carrying gun.
The officer shouted: "Armed police drop your weapon."
He said Moat replied: "Shoot me, f****** shoot me."
If Moat had pointed his shotgun at police, he would have been shot, the officer said.
He calmed down when he realised the officers were from West Yorkshire, the witness said.
"The tone of voice changed and I seem to recall he actually apologised and recognised we had different accents," he told coroner David Mitford.
The first officers talked to Moat for around 25 minutes until trained negotiators took over.
The armed response team carried a G36 Carbine rifle, a Glock 17 pistol and a standard X26 Taser.
The officer stayed at the scene from around 7.15pm to shortly before 1am, enduring heavy rain and midges.
Moat blasted himself at around 1.15am after the officer had been relieved by colleagues.
Mr Mitford asked if the witness felt threatened by Moat.
He replied: "Yes sir. The threat I was faced with at the time was very high.
"Approximately 10m in front of me I have a man armed with a sawn-off shotgun which at that distance is a devastating, lethal weapon. It could easily kill me irrespective of the body armour I was wearing at the time."
Moat kept his weapon pointing at himself throughout, the officer said.
The negotiators encouraged Moat to give himself up, the jury heard.
"He was very lucid. He didn't appear to be struggling to hold a conversation.
"He would argue back to the negotiators, such as 'what sort of life would I have if I gave myself up'."
Moat took up the offer of a sandwich and a bottle of water, keeping his gun pointing at his head throughout, the officer said.
Hugh Davies, representing two West Yorkshire Police officers, asked: "Did he indicate he had any positive reason to live?"
"Not to my knowledge," the witness replied.
Witnesses described the climate of "acute fear" that swept a community during Moat's final moments.
Rothbury resident Peter Avison filmed the killer during the confrontation with police on the banks of the River Coquet.
He heard "two bangs" when the gunman shot himself after the six hour stand-off.
He told the inquest he spotted that the gunman died from the back garden of his home.
He was preparing a barbecue when he saw "a tall gentleman", who was Moat, walking beside the river.
He saw the killer being surrounded by police then lie face down on the riverbank, with his feet to the river and the sawn off shotgun pointed at his head.
He said: "From the perspective of someone who lived in the village and had two small children, we were extremely concerned.
"We were watching absolutely everything, we would not let the children outside, we really thought twice about hanging out the washing.
"It was that level of fear. We were acutely sensitive to any activity in the vicinity."
Mr Avison was live on BBC Radio 5Live when he heard the sound of a shotgun.
He told the radio station: "He's just shot himself."
He told the inquest the first bang was a loud, deep thud, like the sound of the shotguns he had heard grouse shooters using in the Cheviot Hills.
The second was "substantially quieter" and was in his judgment the echo of the first.
The inquest was read a statement by Robert Herdman, whose house backed on to the riverbank, who watched Moat kneeling upright with the shotgun pointed alternately at his right temple, then chin.
Mr Herdman said: "At about 1am I was still watching and I heard a single gunshot, clearly. I knew it was a gunshot. It sounded different to a rifle.
"I then saw him (Moat) move slowly, falling down from left to right.
"This lasted for a few seconds."
The inquest heard that around 10 armed police officers then advanced on Moat's body in a "controlled, professional manner" before shouting "clear" and allowing paramedics to get near.
"Eight or 10 police officers then ran up to him," Mr Herdman said.
"They were all standing or bending over him.
"I presumed they were trying to get the gun off him.
"The ambulance staff then ran in and Mr Moat was taken away and that was the end of it."