A 15-year-old girl has died four days after an arson attack at a house in Tooting.

Maleha Masud, who attended Burntwood School, died last night in hospital.

Her brothers Zain, 22, Junaid, 16, and her sister Nabiha, 21, remain in a critical condition.

Earlier this week their mother, Rubina, asked members of the community to "pray for her children".

The 53-year-old, who was released from hospital on Monday, said: "I am devastated at what's happened. I can't believe anyone would do such a thing. I am just really concerned for my children. Please pray for them."

Helen Dorfman, headteacher at Burntwood School, said pupils were being told the tragic news this morning. She said: "We have held a series of assemblies wit h the students. Burntwood is a very harmonious, close, community. This tragedy has drawn us together even more than before. The mood in the school is very dignified and respectful. We have sent our thoughts and prayers to the family and we will be holding a memorial service for Maleha next week."

Tooting MP Sadik Khan said: "It is really important that anybody with any information comes forward and provides it. This is a lovely family that comes from a humble background and have done really well. They are an inspiration to us all. Local faith groups are praying for the them and all our thoughts are with the family."

The London Fire Brigade was called to the Lessingham Avenue home at 4.30am on Sunday after arsonists poured petrol through the letterbox.

They rescued Nabiha, Maleha and Junaid but Nabiha had to be resuscitated by paramedics at the scene.

Ms Masud and eldest son Zain escaped after jumping from a first floor window.

All four siblings suffered from burns and smoke inhilation.

Two teenagers, aged 14 and 15, were arrested on suspicion of arson and have been bailed.

A Met Police said a murder investigation had now been started.

Det Ch Insp Damian Allain said: "A mother has had her youngest child taken from her in the most tragic circumstances.

"Her three other children remain seriously ill in hospital. They were at the place where they should feel safest, in their family home.

"Whoever has committed this act is not only a coward but is a dangerous individual who must be caught.

"I would appeal to people who may have seen anyone carrying a petrol can or similar container to come forward."

Anyone with information should contact police on 020 8721 4805 or call Crimestoppers anonymously on 0800 555 111.

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