‘Hostile reconnaissance’ is the term used within policing and the security sector to describe observation of a specific target by terrorists or other criminals as part of the planning of a hostile act on that target.11
Between 15th April 2017 and 18th May 2017, SA was in Libya. On 18th May,12 21st May13 and on the afternoon of 22nd May 2017,14 SA visited the Arena to carry out hostile reconnaissance. The times SA visited on these occasions are set out in greater detail in the chronology at Appendix 2. These presented opportunities to detect, disrupt or deter him. Because the CCTV was overwritten, it is not possible to know whether SA visited on earlier occasions prior to 15th April 2017.15
SA’s hostile reconnaissance was conducted at times and in a way which made detecting him a substantial challenge. At these times, he was not carrying his large backpack containing the bomb. Given the extent of the challenge, I make no criticism of any individual for not having detected his hostile reconnaissance on those occasions, particularly bearing in mind the security systems in place at the time.
There existed the opportunity for SMG to make hostile reconnaissance more difficult for SA during events by pushing out the security perimeter of the security operation. This could have been a missed opportunity, depending on how the new security perimeter operated. It may have had the effect of deterring SA from attacking the Arena. I shall address the issue of the security perimeter in greater detail in Part 6.
Setting aside the issue of the perimeter, had things been done better by SMG and Showsec, and had BTP officers been more alert to the possibility of hostile reconnaissance, the prospect of detecting it would have been increased. I will address these weaknesses in Parts 6 and 7.