A man who tried to kill a police officer in a machete attack has been jailed for ten years.

Craig Brown, 31, repeatedly hit out at Sergeant Brian Simpson, who was left fearing for his life last September.

The terrified officer told jurors he had never experienced anything like it in his 19-year career following the incident in Dumbarton, West Dunbartonshire.

At the High Court in Glasgow on Friday, Lord Clark told Brown: "It is a fundamental feature that police officers are there to look after the welfare of others. What you did was utterly contemptible."

The judge highlighted Brown's lengthy record, including a number of convictions for serious assault, which showed he had a "marked propensity for serious violence".

Jurors heard how Sgt Simpson, 44, had been called to someone acting suspiciously in the street.

He was alone when he spotted Brown and initially asked was he okay.

Brown said: "Are you an armed response unit?"

Sgt Simpson recalled: "It was an unusual question. I said 'no'. He then stated, 'well, you better get one'. I knew exactly what he meant as he then withdrew a long machete from his right trouser leg.

"He immediately held it out in an aggressive, threatening manner."

Prosecutors described the machete as a "horrific looking weapon".

Sgt Simpson took out his incapacitating spray to try and ward off Brown, but was told: "You better hope armed police are on their way."

Brown swung the sword at the sergeant's back, just missing him.

Sgt Simpson told the jury: "I was scared. I was there by myself in front of someone telling me to get firearms officers.

"There was absolutely no need to be walking about the streets with it. If that had struck me, it would have caused significant injuries."

Brown also "chopped down" on sergeant Simpson's car and smashed a window before fleeing the scene.

Sgt Simpson told the court: "I have never been threatened with a weapon like this in my service.

"He was trying to stab me with it, attack me. I felt shocked that someone could be walking the streets like that.

"There were a lot of 'what ifs' afterwards, like what if I had not reacted as quickly as I did do. He could have killed me."

Defending Brown, David Moggach said: "He acknowledges that he has been convicted of a serious crime, but his position is that he did not attempt to murder the police sergeant."

Brown will also be supervised for four years on his release.