Absolutely, she had no powers to make you delete your pictures. At the outset of higher security measures a number of incidents arose at railway stations where police officers mistakenly thought they had powers regarding persons taking photographs at stations, they were obviosly thinking of terrorism reconnaissance. Following a number of incidents of this nature officers were briefed regarding the absence of any powers to make people delete their photographs. In the case of any suspicion of terrorism reconnaissance then the suspected offender would have ben arrested and camera becomes evidence together with its contents.