While chasing down the scattered pages of the journalist's
notes, Alex collects several in one hand. He quickly scales a wall to retrieve another one, but as he comes over the top both hands are inexplicably empty. Seconds later he's picked up one sheet, but he's holding a bunch of pages again.
It can take weeks to fully investigate the cause of a fire. So the officer saying they know how it started 3 mins afterward is bunk.
When discussing the explosion, the British Police officer mentions the fire department. In the UK, it is referred to as the Fire Brigade.