Police used stun guns on Raoul Moat

• Heavily armed police negotiate with gunman Raoul Moat before the fugitive shot himself. Photogtraph: Dan Kitwood/Getty Images

The dramatic details of Moat's final hours emerged as eyewitnesses claimed officers had "jumped" on the man in the seconds before he turned his gun on himself.

The officers fired the stun weapons, which incapacitate their target, but Moat still managed to shoot himself in the head, bringing the week-long manhunt to a close.

The Independent Police Complaints Commission (IPCC) will now conduct an investigation into the police's handling of the stand-off, which Northumbria Police had hoped would end with Moat's safe capture.

Part of that investigation will focus on when and why two electronic stun guns were discharged during the dramatic last stand.

Investigators will want to know whether the deployment of Tasers prompted Moat into killing himself.

Northumbria Police topped a recent league for the number of incidents in which a Taser was aimed or used. The force reported even more incidents involving stun guns – 704 between April 2004 and August 2009 – than the Metropolitan Police, which covers a population more than five times larger.

The dramatic shoot out at 1:15am yesterday came almost a week after Moat's former girlfriend Samantha Stobbart, 22, was shot and injured, her boyfriend Chris Brown, 29, was shot dead and Pc David Rathband was fired at and seriously injured in his patrol car.

A huge manhunt, which included the use of an RAF Tornado, followed only for police to finally find the nightclub doorman on a riverbank just outside the village of Rothbury, Northumbria. The six-hour stand off that began on Friday evening will now become the focus of the investigation.

Yesterday afternoon, Northumbria's acting chief constable, Sue Sim, said: "At around 1.15am, from information available at the moment, it appears the suspect shot himself. It appears no gunshots were fired by police officers." She added: "Right up until that time, police officers were striving to persuade Mr Moat to give himself up peacefully. During this time, officers discharged Taser, however, this did not prevent his death. At around 2.20am he was pronounced dead at hospital."

However, it was confirmed later that two officers had fired their Taser guns at Moat, although it was unclear last night when the stun guns were fired. Tasers deliver electric shocks of up to 50,000 volts, which are intended to be a less lethal alternative to conventional firearms and are meant to temporarily paralyse a target.

One eyewitness said police had jumped on 37-year-old Moat before the gunshot rang out, suggesting they may have decided to bring matters to a close.

IPCC Commissioner Nicholas Long said: "Early indications show that gunshots were not fired by police officers and this will, of course, form part of the IPCC investigation. It is also understood that a police officer did discharge a Taser and our investigation will also look at this."

The inquiry will also involve a wider investigation into Northumbria Police's handling of the affair, amid growing criticism of their conduct following Moat's recent release from Durham prison.

After that release, on 1 July, prison staff warned police he might intend to cause serious harm to his former girlfriend, but he was able to move about freely.

Long added: "The IPCC has now two independent investigations. The first relates to the intelligence from the prison authorities on Mr Moat's release and the second to his death. I have decided that there will be one investigation covering both these aspects.

"We will be examining whether correct procedures were followed by Northumbria Police and the detail of how this incident came to a conclusion."

He continued: "A full investigation will now be carried out and we will publish our findings in due course so that there is a public account answering the many questions that people will have."

Police also faced criticism when it emerged that officers were aware that Moat had visited the home of his friend Andy Mcallister on Saturday, 3 July. But they were not at the Newcastle address when Moat returned in the early hours of last Monday.

It was during the second visit that he delivered a "murder statement" in which he declared war on the police.

Mcallister said it took officers "more than an hour" to arrive after he dialled 999. "They knew he'd been to my house once – I thought they would have been watching," he said.

It was also questioned why it was not until Monday night that police released details of the black Lexus saloon car that Moat had been using.

Residents of Rothbury said the vehicle had been parked in a car park beside the River Coquet for at least ten hours before they knew police were looking for it.

Police leading the manhunt yesterday admitted they had been pressed to the limit in the search for the gunman, in what was one of Northumbria Police's biggest-ever operations.

Det Ch Supt Neil Adamson added: "The past seven days have been challenging, to say the least. We were faced with a series of extraordinary events, which have tested the resolve and professionalism of all involved."

He added: "The information, intelligence and advice available to me, always led me to believe that Moat was in and around the Rothbury area, constantly on the move. My inquiries were frustrated by a number of significant challenges, including apparent support and assistance for Moat from third parties."

A forensic examination of the scene where Moat died was ongoing yesterday.

The investigation was also focusing on an area close to a culvert near the River Coquet, where it is thought that Moat had hidden from searchers.

Moat had been on the run for a week after shooting Stobbart and killing her new partner, Brown.

The attacks took place in the Scafell area of Birtley, near Gateshead, on Saturday, 3 July, just 48 hours after Moat was released from prison, after serving an 18-week sentence for assault.

In the early hours of Sunday, 4 July, Moat then allegedy shot Pc David Rathband as he sat in his patrol car in East Denton, near Newcastle.

The manhunt to track down Moat is believed to be one of the most expensive in British police history after the gunman evaded officers for nearly a week.

Northumbria Police are expected to be left with a bill for more than 3 million after they drafted in about 10 per cent of the UK's specialist firearms officers.

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