More than 200 investigators were urgently working to determine the significance of ‘C’ and whether the killer had accomplices or links with a terrorist network.
Bundles of flowers and notes mark the spots where people's bodies were found in NicePlay!00:32
Seven people including a woman were in custody on Sunday night after the arrests earlier in the day of an Albanian couple suspected of aiding Bouhlel, described by the Islamic State of Iraq and the Levant (Isil) as one its “soldiers”.
He sent a flurry of texts shortly before the attack. Another one, saying “I’ve got the material”, was sent to one of the men in custody, whose identities have not been made public.
Bouhlel fired a 7.65mm automatic handgun at police before they shot him dead on Thursday night. Other weapons found in the lorry turned out to be fakes or replicas.
CCTV cameras on the Promenade des Anglais, the scene of the massacre, captured Bouhlel twice in the two days before the attack driving the lorry as he scrutinised his surroundings, apparently preparing how best to execute the attack.Bouhlel's phone is said to be full of messages, videos and photographs, including ones of men and women he had recently slept with.