CLEAN : Witnesses describe London tube fireball

The transcript describes a chaotic scene following a massive explosion, where a fireball approaches rapidly. People react with panic, considering the possibility of further attacks. Amidst the chaos, they attempt to escape, running from the fireball and jumping to safety, driven by survival instincts.

What thoughts crossed the narrator's mind regarding potential attackers?

What does the narrator imply about the urgency of the situation?