in addition to riad khan, who was the target of the strike who i.s.i.l. associates were also killed one of whom raol hamin was identified as a british u.k. national. >> main advisor to the u.k, first acknowledged strike strike on syrian soil by the british. over the past year, britain has carried out 288 air strikes on iraq against i.s.i.l. fighters. but two years ago, britain's politicians flair owely voted against carrying out military action in syria. >> 272, the nos to the left 285. >> reporter: the legality of killing two british nationals way will be scrutinized. >> on the grounds of self defense, against who? there is a huge question about whether there is a right of self defense against terrorist groups and the timing of those events as well. the only way to your these strikes is -- to justify these strikes is on this basis. it would have to be a pretty profound change in the u.k.'s stance of self defense. the strike on raid khan will be seen as controversial not the least because of the gray area surrounding the legality of crossing the border an