Dangerous London radical Brusthom Ziamani has been sentenced to 22 years in prison for plotting to behead a British soldier in a copycat murder inspired by the slaughter of Lee Rigby.

The 19-year-old, of Camberwell, south London, who was 18 at the time of the offence, planned to kill a soldier and told police he also wanted to attack Prime Minister David Cameron and fly the black flag of Islamic State over Downing Street.

The Old Bailey heard how Ziamani constructed a plan to decapitate a member of the armed forces, or a government official, and display the severed head for photography.

He was found guilty last month after being arrested in east London months after he converted to Islam in August 2014, while on his way to commit a massacre, and was sentenced today.

Brusthom Ziamani
Police said Brusthom Ziamani's views became more apparent on his social media accounts Met Police

Police found the extremist to be carrying carrying a 12in (30cm) knife and a hammer in his rucksack.

Earlier in the year, police searched his property as part of a separate incident and found a handwritten letter by Ziamani that revealed his deadly intentions to maim a solider and die a martyr.

Other parts of the letter glorified the murder of Rigby, who was cut down outside Woolwich Barracks in May 2013 by Michael Adebolajo and Michael Adebowale, and stated that "we should do a 9/11, 7/7 and a Woolwich all in one day".

Deb Walsh, deputy head of counter terrorism at the Crown Prosecution Service, said: "Brustholm Ziamani is a highly dangerous individual and this country is significantly safer as a result of this conviction.

"This case highlights how violent and extreme views on a page can become credible threats to the lives and safety of British citizens.

"This successful conviction is testament to the work of our dedicated counter-terrorism prosecutors who, with police colleagues, are determined to play their part in the fight against terrorism."