service. the british prime minister tweeted about the situation my thoughts are with everybody affected in glasgow and the emergency services working tonight. >> richard quest joining us again live by phone. richard, a terrible situation. it's still very early in this case. but is there any idea of what caused this crash? >> reporter: no, absolutely not. all we know from eyewitnesses is that a helicopter from the port, a police helicopter, was over the area at the time. and then according to eyewitnesses appeared to lose power. some say they heard it turning. and others say she heard the sound of an engine sputtering. one eyewitness said she saw it on the roof and then fall through the roof. why the helicopter suddenly lost height, what happened with the engine, fuel, we just don't know. and we also don't know, george,