Fox News and other channels are showing amateur videos of the firefighting efforts after the crash. It appears that civilians are helping with the hoses. Perhaps they are off-duty officers and firefighters, since it was mentioned that many police officers and firefighters live in that community, but it's also likely that they were just residents. That video reenforces my American pride.
You are correct. This is an extremely tight neighborhood. Many,many NYC workers live there. Firemen, cops and Sanitation workers. People who grow up there don't usually leave.
I also heard much earlier on Fox that no one was running away from the fires, but were in fact running towards homes to try to help their neighbors. The Police are trying to keep people from doing that.