Scene where MP David Amess was stabbed
Scene where MP David Amess was stabbedREUTERS/Andrew Couldridge

A jury deliberated for just 18 minutes on Monday before finding an Islamic State (ISIS) supporter guilty of stabbing British lawmaker David Amess to death last year, The Associated Press reported.

Ali Harbi Ali, 26, was found guilty by London’s Central Criminal Court of murder and preparing terrorist acts.

Ali stabbed the veteran British lawmaker to death last year while he was meeting with voters at a church hall in eastern England.

Ali, who had spent years researching and planning potential attacks on lawmakers, had defended his actions by saying Amess deserved to die as a result of voting for airstrikes on Syria in 2014 and 2015, according to AP.

At the time of the murder, Amess had been a member of Parliament for Southend West, which includes Leigh-on-Sea, since 1997, and had been a lawmaker since 1983, making him one of the longest-serving politicians in the House of Commons.

His murder came five years after another MP, Jo Cox, was murdered in her small-town constituency by a man linked to a neo-Nazi group.