TEMPO.CO, Jakarta - Prime Minister of England David Cameron said that he will retaliatory measures in response to the execution of reporter British journalist David Haines by the Islamic State (IS) rebels.

"We will do everything in our power to hunt down the killer and make them face justice no matter how long it takes," said Cameron in his Twitter account yesterday shortly after the IS uploaded the video of the execution on the internet.

Cameron claimed that the IS is a plague that must be eliminated and that the execution of Haines is purely a crime on its own.

The video of the execution was posted on IS's website last Saturday. The 44-year journalist from Perth, Scotland, was kidnapped a year ago during his humanitarian aid visit to Syria. He was being held hostage in Atmeh Village, Syria since March 2013.

The video showed a man in black clothing wearing a mask standing behind a man who is presumed to be Haines. The video titled "Message to US Allies" is the answer to the aid provided by England for the Iraqi and Kurdish army, the Peshmerga, to help in the battle against the IS. The video is similar to the execution video of two American journalists, Steven Sotloff and James Foley.

CNN Military Analyst Lieutenant Colonel Rick Francona said that the execution is a ploy by the IS to interfere with the cooperation between the US and England. "The actions by the IS guarantees the joint operation between the US and England at all levels,” he said.

REUTERS | TELEGRAPH | CNN