one of the reasons that subletting a council property causes problems is because when there is any sort of incident, like this but could be others like a broken gas main/toxic fumes etc - there is no real idea of how many people are involved, how many are safe and how many are not. it puts the lives of firefighters at risk because they then don't know how many are in the house, street or building.
the rules on overcrowding get ignored and they are there not just for decency reasons in terms of people sharing rooms but because over crowding causes a fire risk. why? because 4 people in a property have less electrical devices and things plugged in than 10 and the more people the more overloaded the system becomes.
I dealt with the aftermath of fires in HMO's in London only a couple but I still remember the smell after all these years.
what has happened is horrific but we need to see the response as a staged process.
first off who was in there and how many with any amnesty that is necessary to find this out. second, if the flat is sublet then I want to see the original tenants who did this in prison, not fined or slapped on the wrist but locked away to send a clear signal of how dangerous this is.
It is far far too easy for tenants to sublet council properties and this needs to be very much tougher. but now is not the time to think about this only to make sure that it does happen in the very near future.