Redcar MP Anna Turley said the community had faced a “profound amount of heartbreak over the past few weeks”.
She said: “I am devastated to hear of the tragic loss of life following this morning’s fire in Grangetown.
“My deepest condolences are with the families, friends and loved ones of those who have died, and my thoughts are also with those injured and receiving treatment.”
Grangetown councillor Adam Brook urged people not to speculate.
He said: “Many residents have been in touch with me throughout the morning, and I know there is understandably a great deal of concern.
“However, I would urge people not to speculate or share unconfirmed information.”
The families of the people involved have been informed and they are being supported by specialist officers.
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