A Manchester fire chief said it was "too early" to say what led to firefighter Stephen Hunt's death as he tackled a blaze in the city yesterday.
Steve McGuirk, county fire officer for Greater Manchester Fire and Rescue Service, said:
It doesn't look like a building collapse or that he fell through any floors. The early indications are an absolutely massive, ferocious and sudden build up of heat.
But where that came from and what caused that we have got absolutely no idea at this stage. That's really the purpose of the investigation that we are now engaged in.
More top news
Molly Smith, 5, won £500 after her accidental selfie with a snowman caught the attention of competition judges.
Harry Street, formerly Barry Williams, shot dead five people in a spree across the West Midlands in 1978.
The Interview, the Sony film about a fictional plot to assassinate North Korean leader Kim Jong Un, has made more than $15m in online sales.