An A-level pupil accused of murdering a school student support officer was cleared amid claims that the alleged victim was a “predatory paedophile”.

Muhammad Amirul Haq, known as Amir, died following a knife wound to the heart in his room at his family home in Poplar, east London last November.

The 17-year-old defendant admitted wielding the kitchen knife that fatally injured Amir but said he had feared being raped or killed by him.

He said the blade went into the 27-year-old when he “lunged” at him as he tried to flee from the room.

Tower Hamlets Council said it would be now be looking into the allegations about Amir, who worked at St Paul’s Way Community School.

An Old Bailey jury heard that he was “outwardly religious” but was secretly bisexual and had had a number of male partners.

It was further claimed that he invited the teenager and another boy to his room to smoke shisha pipes with him before showing them pornography and encouraging them to let him carry out sex acts on them.

Brian O’Neill QC, defending, told the jury: “Amir displayed all the outward signs of respectability. He had an arranged marriage, he wore a religious hat and sported a beard.

”He went to mosque and prayed and encouraged others to do the same. He performed charitable deeds. He had a job at a local school. But all of that was a sham.

”The truth was that Amir was a predatory paedophile who preyed on young boys in his own community and groomed them in order that he might sexually assault and rape them.”

The defendant, who cannot be named because of his age, was described as a “devout, humble Muslim” who wanted to become a human rights lawyer by teachers at his school - not the same one where Amir worked.

He was unanimously cleared of both murder and manslaughter by the jury.

The teenager said he had brought a knife with him when he went round to see Amir in case he tried to force him “into sexual acts”.

He told the court that he produced the weapon after Amir gripped his arm and put his hand on his crotch.

The boy said he told him to “back off” and tried to get out of his room but the door would not open.

Amir was trying to persuade him to “help” him and “sounded very fearsome and very forceful”, the teenager said.

”I genuinely thought that he would either rape me or if I refused he would kill me,” he added.

”I produced the knife. As he was holding my arm I brought it out and held it in front of me.

”He said ‘help me this time and you can leave’. I told him to back off and let me go. He said ‘what are you going to do?, there is nothing you can do, no one will believe you’. He lunged towards me.”

Asked what happened with the knife, the teenager told the court: “I believe it went into him.”

Amir staggered onto his bed and died a few hours later in hospital.

The teenager fled but was arrested at home shortly afterwards, and admitted in a prepared statement to wielding the knife, telling detectives he had “flipped out” at the older man’s actions.

Jurors rejected the claim by Victor Temple QC, prosecuting, that the teenager was being “vengeful” and “knew full well what he was doing”.

In his evidence, the boy said Amir would hang around at the gym where he and his friends worked out and would sometimes touch them.

He said the older man distributed presents, giving him a mobile phone, and once tagged along when they went to Chessington World of Adventures. Amir would also invite them round to smoke shisha, he added.

The boy said it was “a little strange” but at first did not suspect Amir might be sexually attracted to him and his friends.

He said Amir’s expressed view on homosexuality had been “very negative” and he had said there was “no space in society for gay people”.

The defendant himself, who jurors heard had a girlfriend, said he had “nothing against homosexuality”.

He said Amir had told him that he had a “fertility problem” and wanted him to donate sperm into his mouth.

The boy said that he had made him swear on the Koran to keep it a secret and that if he did not he would tell other people that he - the boy - was gay.

Mr O’Neill, defending the boy, said: “There can be no doubt but that this is a tragic case.”

But he added: “There is no denying the fact that [the boy] would not have felt compelled to carry that knife if Amir had not been sexually abusing him.

”A young man such as the one you have seen and heard about must have reached the very depths of despair to have taken that knife with him that Sunday afternoon.”

He added: “The death of Amir was a dreadful, dreadful accident.

”[The boy] had produced the knife as a last resort to enable him to make his escape from that room. He genuinely and with good cause feared that he would be raped by Amir if he did not get out of that room.”

After today’s verdict, Judge Jeremy Roberts expressed his condolences to the relatives of the dead man.

He said: “It was tragic for everybody that it happened in these circumstances.”

Tower Hamlets council said in a statement: “This is a terrible case where a man has lost his life and a young person has faced serious charges.

”Prior to this court case, neither the council or the school had received any allegations of improper conduct.

”We have a duty of care to ensure the safety of children and young people in our borough and would have fully investigated any such allegations had they arisen.

”We will now be looking into the allegations that have come to light during this court case.

”Whilst we cannot comment on individual members of staff, we can confirm that all appropriate checks were in place prior to Mr Haq’s employment.”

By John-Paul Ford Rojas