Michael Steven Sandford
Michael Steven Sandford is arrested at the Donald Trump rally in Las VegasDavid Becker/Reuters

The 20-year old who was arrested after allegedly attempting to grab a police officer's gun in order to shoot Donald Trump has been named as British man Michael Sandford.

Sandford, who is facing a 10-year prison sentence if he is found guilty of attempting to kill the GOP candidate, was arrested at a rally in Las Vegas on 20 June.

The former student of Ascombe School in Dorking, Surrey, had reportedly been living in the US for around 18 months, and was sleeping in his car after his visa expired.

He initially lived in Hoboken, New Jersey, on arriving in the US, and then moved to California, from where he is believed to have driven to Las Vegas intended to shoot Trump, according to a federal complaint filed by the US attorney for Nevada and carried by US news outlets.

He told police he had plotted to assassinate the Republican candidate for a year. He had taken shooting lessons in recent days, and had believed he would die during the bid.

After allegedly attempting to grab the gun of a police officer at the Trump rally, Sandford was arrested and has been charged with "an act of violence on restricted grounds".

He is believed to suffer from a form of autism and had a mental health breakdown in the past.

According to the Mirror, Sandford was a highly intelligent schoolboy who was "obsessed" with the TV series Rbot Wars. He bought robots which had appeared in the show, and rebuilt them for live roadshows linked to the event.

John Findlay, a expert behind the original show, said he had bought and sold robots to Sandford until he suddenly "disappeared". Mr Findlay told The Mirror: "I'm totally shocked. When I saw his picture it was just totally freaky.

A friend of the family told The Mirror Sandford's mother Lynne was devastated after being told of what happened by a friend who had seen it on the news.

She said: "She has worked so hard to get her son through his problems and has another little one to take care of this will be far too much for her.

"She's switched off her phone and won't want anything to do with the world now, she's just distraught.

"Her son always had very serious problems. He had a complete mental breakdown about six years ago and nobody has seen much of him since.

"He'd only come out at night because that's when he felt most safe I think but the family thought he was through the worst of his troubles.

"They thought he was on the mend out in the States so this is just absolutely shocking."

In a statement, Las Vegas Metropolitan Police Department (LVMPD) said: "While inside the theatre, a subject, later identified as 19 year old (sic) Michael Sandford, approached a uniformed LVMPD officer who was assigned to the event. Sandford began a conversation with the officer under the pretence that he was seeking an autograph.

"During the conversation, Sandford attempted to disarm the officer. The officers assigned to the event were able to quickly take Sandford into custody with little further disruption at the venue. Custody of Sandford has since been handed over to the United States Secret Service where he will face formal charges."