The firefighters who tried to rescue residents as they tackled the Grenfell Tower blaze could face future psychological issues, London Fire Commissioner Dany Cotton has warned.
She said the tough conditions and shocking scenes they faced, including a child being thrown from a window, had traumatised many.
London Fire Brigade said more than 200 firefighters and 40 fire engines attended the scene after the blaze ripped through the 24-storey block in west London, from the second floor upwards.
She told Sky News: "They were in and out of that building, committing time after time to rescue the people we knew were in there. There was never any hesitation.
"As the commissioner of the London Fire Brigade I was truly anxious for a long time about the safety of the building and my firefighters in there, but they were never going to stop until they physically could not get in there any more.
"The thing that worries me going forward is the psychological effect. A lot of my firefighters yesterday experienced things they have never seen before.
"I spoke to some people who were truly distressed - not least because they knew there were people still in there and they were battling through the heat to get there.
"What happened yesterday truly traumatised a lot of people."
The firefighters "were in fear of their own lives" as they went into the building which was "alight from top to bottom", according to Ms Cotton.
She said the firefighters had been particularly affected by the desperation of one family who threw a baby from a window in a bid to save it.
She told Sky News: "For my crews who were on the ground who witnessed it happening it was truly horrible and shocking.
"I spoke to one of my officers who was very near when someone came out of the window, he was in tears. He is a professional fire officer.
"We like to think of ourselves as roughty-tufty and as heroes but they have feelings. People were absolutely devastated by yesterday's events."
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