A British court on Wednesday sent a stern warning to thugs using social media to incite riots by sentencing a man to four years in jail after he admitted inciting public disorder on Facebook during riots in England.

Jamie Counsel, 25, set up a page called Bring the Riots to Cardiff, later changed to Bring the Riots to Swansea.

The sentence should be a warning that anyone using modern media to incite riots would face stiff punishment, said the judge at Cardiff Crown Court.

Judge Nicholas Cooke said the terror caused by the riots was "incalculable".

The court heard that he created the page on August 9 as rioting hit London and other cities such as Birmingham and Bristol.

Daniel Webster, prosecuting, said Counsel's page had specified a time and location for the violent disorder to take place.

Initially, 36 people joined the page, with one writing about plans to target the House of Fraser store in Cardiff.

A further 35 people joined the page when it was renamed to refer to Swansea, the BBC reported.

He was arrested on August 10 after concerned members of the public contacted the police.

A wave of rioting, looting and arson spread from London to parts of the East and West Midlands, Merseyside, Bristol, Manchester and Gloucester from August 6 to 9 after a 29-year- old youth was shot dead by police in Totterham.

Sentencing him to four years, minus 96 days spent on remand, Cooke told Counsel: "The violent disorder cost vast sums of money... the terror to the public is incalculable."