London ( CNN ) -- Security experts are starting to analyze events leading up to the horrific cleaver attack of a man believed to be a British soldier on the suburban streets of London . One key line of inquiry they 'll be following among the many leads : How does this attack relate to other incidents around the world ? CNN Terrorism Analyst Paul Cruickshank says the precedents are not hard to detect . `` It 's early in the investigation in terms of looking at the culprit and motivation but there 's a track record of Islamist extremists inspired by al Qaeda ideology targeting soldiers in the West , '' he said . Other areas the security services would look at , he added , would include which groups -- if any -- were behind the attack and whether it was home-grown . Cruickshank said that there had been plots in the past when attackers had tried to target military personnel : the fact that Wednesday 's murder happened near a military barracks in southeast London was significant . `` It 's not clear if this particular officer was specifically targeted or he just happened to be walking through this area and was a target of opportunity , '' said Cruickshank , `` but it seems that more than one individual was part of this attack , so this could well have been planned . We just do n't know . '' CNN affiliate ITN has broadcast a video showing a man at the scene of the attack with bloody hands and holding a meat cleaver , saying : `` We swear by almighty Allah we will never stop fighting you . '' He then continues : `` The only reasons we killed this man this is because Muslims are dying daily . This British soldier is an eye for an eye , a tooth for tooth . '' Cruickshank cited the plot , uncovered in 2007 , to kidnap and murder a Muslim British soldier . Four men plotted to kidnap a solider on leave and then decapitate him in a garage . Parviz Khan , the leader of the plotters , planned to behead the soldier `` like a pig '' and then post film of the killing online . It is not known if there are any links between this plot and the attack . Leading al Qaeda clerics have called those who target soldiers in the West `` heroes , '' Cruickshank said . `` These are people inspired by al Qaeda ideology in the West , '' Cruickshank said . `` Hero '' was the term militant cleric Anwar al-Awlaki -- who was born and raised in the United States -- had used to describe Nidal Hasan , an American Muslim soldier based at Fort Hood , Texas . In November 2009 Hasan shot and killed 13 U.S. soldiers at the military base in November 2009 . Hasan and Al-Awlaki had communicated on the internet before the shootings at the military base , used at the time by soldiers about to be deployed to Iraq and Afghanistan , Cruickshank said . Al-Awlaki himself was killed by a U.S. drone strike in in Yemen in September 2011 . `` The motivation in these past attacks has been the war in Afghanistan and Iraq , '' Cruickshank said . `` For a generation of Islamist extremists in the UK , Iraq and Afghanistan were their formative experiences . '' In 2012 , Mohammed Merah , a 23-year-old French-Algerian , went on a killing spree that terrorized France and left seven people dead , including three soldiers . Three children were killed when he attacked a Jewish school . He was eventually tracked down to his apartment in Toulouse , southern France , where he was besieged for 32 hours before being killed as security forces stormed the building on March 22 . During that siege Merah told negotiators that he was acting on behalf of al Qaeda . A senior U.S. counterterrorism official later told CNN that Merah was believed to have linked up with Jund al Khilafah , an obscure Kazakh Jihadist group with ties to al Qaeda , just months before the attacks . ] . Cruickshank said the fact that such killings had occurred since foreign troop levels in Iraq and Afghanistan had been scaled back was irrelevant to the attackers . `` The Iraq War is still very much an issue for these people . A significant number of these have been energised by watching beheading videos put out by groups like al Qaeda in Iraq . '' Monica Sarkar contributed to this report .
Cruickshank : Track record of al Qaeda-inspired extremists targeting soldiers . British police uncovered 2007 plot to kidnap and murder a Muslim British soldier . Security services looking at whether London suspects linked to any groups . Leading al Qaeda clerics have called those who target western soldiers 'heroes '