>>> the city of houston has suffered a terrible tragedy. starting with an awful rolling, raging fire in a hotel that started in an adjacent restaurant. in terms of the death toll here, they have suffered the biggest loss of firefighters in a single fire in the city's history. several remain critical tonight. nbc's anne thompson has our report.
>> reporter: the blaze started in a restaurant and quickly spread to the neighboring southwest inn. hotel fires are among the most difficult to fight. dreaded because the beds and curtains act as additional fuel in an already dangerous situation. with wind gusts up to 25 miles per hour the black smoke snarled traffic on u.s. 59 , one of houston's most heavily traveled expressways. but the tragic toll was at the scene. as flames consumed the structure, the roof collapsed. frantically the firefighters tried to save their own.
>> protect and watch out for each other so when we have something as devastating and as sudden as a collapse that's when we have the potential to have many firefighters at one time.
>> reporter: four firefighters were killed, six others injured. video shows many firefighters being treated for what appears to be heat exhaustion . 45 guests were registered at the hotel. it is believed tonight none of them were injured. anne thompson , nbc news.
