The two cousins who murdered the Masud sisters turned on each other at the Old Bailey during the six week trial.

Akmol Miah, 15, from Thornton Heath, torched the Tooting home of Maleha Masud, killing her and elder sister Nabiha, 21, who was engaged to be married.

He enlisted the help of his cousin Shihabuddin Choudhury, 21, who drove down from his home town in Nottingham to help “get revenge” after Maleha split with him.

Both were convicted of two counts of murder and three counts of attempted murder at the Old Bailey this week.

In the Wandsworth Guardian next week you can read a special investigation into the fire:

• How Tooting’s youths helped solve the horrific murder.

• More family reaction and a tribute to the sisters. “I was too ill to be told my sisters had died”.

• Policeman leading the investigation describes how they got their man.

The prosecution claimed Miah recruited Choudhury to help him start the blaze through a series of phone calls and that Choudhury then asked the third defendant, Rasal Khan, to drive him to London.

The court was shown footage of Khan and Choudhury driving from the Midlands to London to collect the teenager before travelling to Tooting.

CCTV, which was shown to the jury, captured the car's journey across London before arriving in Lessingham Avenue and phone evidence showed Choudhury talking to Miah several times during the journey south.

Along with the petrol can found in his house, the most incriminating bits of evidence against Miah was on a computer in his house.

When police searched it they found someone had searched the internet for “how to burn someone's house down”.

He also had a photo of the burnt-out house saved as his screensaver.

Miah admitted it was him who was on the internet but said Choudhury asked him to search for it about 16 hours before the attack.

Miah said he had “suspicions” Mr Choudhury had been involved in the fire.

He said: “I asked him [Choudhury] several times about the fire. I asked was he involved, had he done anything to cause the fire. He said ‘I’m busy, I’m busy, I’ll call you later’.”

The boy also admitted he lied to police when they asked him whether he had any idea who else could be involved.

“I didn’t tell them [the police]. [Choudhury] told me to type in those words, and I put two and two together and thought I might be involved somehow. I was suspicious but I didn’t know for a fact, I wanted to confront him myself. If you think about it from my view I had no knowledge of the fire and I wanted to know for myself,” he said.

“Because I knew that [the defendant] suggested for me to type in these words, If I said I was using the computer then . . . . [the defendant] would be mentioned”.

Choudhury said this was lies and he what his cousin was doing but got cold feet when they got to Lessingham Avenue.

He said he and Khan drove from the Midlands and picked up Miah from his home before the attack - a claim Maih said “was not true”.

Khan said he was paid petrol money to drive Choudhury from Nottingham to the house in Thornton Heath but never discussed the fire with Choudhury.

After picking up Miah he claims he was instructed to drive to Lessingham Avenue via an all-night supermarket where he brought matches.

Khan then drove to the Masud's street where he said Miah and Choudhury told him they wanted to “drop something off”. Khan said: “About five or six minutes later, I'm not sure how long, they ran back. Another man was walking past, not fast, behind my car, going away. 'I asked Choudhury why are you running back. He said he was chased by a drunk man.”

Khan later told police he had “no idea” what the pair were going to do and he was “shocked” to hear about the deaths.

“I would never have agreed to drive [them] had I any idea what they were going to do,” he said, “I'm totally shocked at finding myself in this position.”

Choudhury also told police Khan had thrown the lit match through their letter box on Lessingham Avenue but Khan dismissed the accusation.

“That's a lie. Why would I do something like that? '[Choudhury] just tricked me,” he said. “I know what's right and what's wrong. I've got a family. I know how it feels to lose someone - my brother died in an accident. He died. I know how it feels. I can see the pain my mum and dad go through. I know how it feels to lose someone. I've got sisters. Why would I do something like this?”

The jury agreed with Khan, who wept as he was cleared of all charges.