Members of a family, who died in a suspected arson attack on a house, have been named.
Sabah Usmani and her sons Sohaib, 13, Rayyan, 6, and daughter Hira, 11, died in their end-of-terrace house in Barn Mead, Harlow, Essex, at about 1am on Monday morning.
A third son, Muneeb, 9, and daughter Maheen, 3, were rescued by fire crews and taken to the Princess Alexandra Hospital in a critical condition, where one has since died. The fifth child remains in a critical condition.
A man is also being treated for minor injuries.
Senior investigating officer Detective Superintendent Rob Vinson said: "This is still the early stages of our investigation into the tragic deaths of five members of one family - a mother and four of her young children.
"At this time we are investigating to see whether this fire was started deliberately and need anyone with information to contact us."
The house will be forensically examined to find out how the blaze started.