The Three Choices...

[blim]

I would call the fire brigade. Standard procedure states that when a fire breaks out, medical assistance must be provided and called to the scene in case of injury. Police are also required to show up in the case that it turns into an arson investigation.

This does not work when you call the ambulance or the police straight.

Thats pretty much what i was gonna say, P.S. if the killer had a gun i wouldn't mention it, in the UK armed response takes longer

EDIT: pretty sure the ambulance or police would notify others if you mentioned they were needed