A terrorist who launched an attack after being released from prison declared that he was “not finished with non-believers” days before he was freed.
It came 10 days after he was released from prison after serving a sentence for terror offences, having encouraged his girlfriend to behead her parents and declared his own wish to carry out an attack.
Detective Superintendent Dominic Murphy, of the Metropolitan Police Counter Terrorism Command, said Amman “appeared to retain his extremist mindset and wish to carry out an attack” while in prison.
He had originally been arrested in May 2018 on suspicion of planning a terror attack, but was charged with lesser offences relating to Isis propaganda.
In December 2019, handwritten notes were found in his cell that appeared to show a pledge of allegiance to the leader of Isis, Det Supt Murphy said.
Amman was put in segregation after joining a protest at HMP Belmarsh in January 2020, and police received a report that he told a fellow inmate he was “not finished with these non-believers yet”.
The inquest heard that a senior Metropolitan Police officer expressed concerns about Amman’s release to prison officials and asked if his sentence could be extended, but was told it could not.
He was released automatically on 23 January, placed in a probation service hostel in Streatham and subjected to a curfew, electronic tag and several licence conditions.
He immediately became the subject of a “priority investigation” by MI5 and the Metropolitan Police, the inquest heard.
They initially put Amman under daytime surveillance by undercover officers because of concerns he might commit another offence, and on 29 January the officers were authorised to carry guns.
Two days later, Amman was seen looking at knives in a shop and purchasing items that could be used to make a hoax explosive belt, and the operation was upgraded to 24-hour armed surveillance.
Opening the inquest into his death on Monday, coroner Justice Nicholas Hilliard told jurors that Amman was being followed by four undercover armed police officers on foot when he launched the attack, while others were in vehicles on surrounding roads.
The Royal Courts of Justice heard that the officers were watching as Amman entered a shop on Streatham High Road called Low Price Store and one moved close to the entrance.
“Inside the shop, Amman grabbed a 20cm kitchen knife from a display and ran with it from the shop, removing the packaging quickly,” Justice Hilliard said.
“He ran north on Streatham High Road with [undercover officer] BX87 running behind at 15-20 metres and shouting for him to stop.”
Within seconds, Amman stabbed a woman in the back outside a pub and shortly afterwards, struck a man in his torso. Both victims survived.
As he ran past a Lidl supermarket a second police officer chasing Amman opened fire but missed him and shattered a shop window.
Amman ran on until stopping outside a Boots chemist and turning to officers while holding the knife, at which point he was shot twice.
He was pronounced dead at the scene, following an attack that lasted 62 seconds in total.
Like other terror attacks that happened previously at HMP Whitemoor and Fishmongers’ Hall, he was wearing a homemade fake suicide belt.
The inquest heard that Amman was born in Coventry to parents who had come to the UK as refugees from Sri Lanka, and moved to London as a child.
He was referred to children’s services over mental health concerns in 2014 and moved to a school that offered additional support for challenging behaviour the following year.
Amman was arrested in 2016 for attacking another pupil with a weapon, but not charged because the victim refused to support a prosecution, and was excluded from school for fighting in 2017. That year, he was also arrested for assault, making threats with a weapon and making threats to kill.
A friend later told police that Amman said he had spent most of the time in his cell reading the Quran and had “changed from that time”, starting to pray regularly, grow a beard and wear a religious hat.
School and social work records included incidents of cannabis use and violence, and concerns around Amman’s “anger issues”.
The inquest heard that he was referred to the government Prevent counter-extremism programme in June 2017 but the information “didn’t meet the threshold” for ideological intervention.
Records showed Amman starting to express fears of police labelling him as a terrorist and express anger about the Syrian civil war and treatment of Muslims around the world.
In May 2018, he was arrested by counter-terror police after being identified as the user of a Telegram account that had posted Isis propaganda and urged attacks on a pro-gay rights speaker.
Police who investigated the Streatham attack said they did not find evidence that anyone else was involved or informed of Amman’s intentions.
Isis claimed responsibility for the stabbing the following day, but Det Supt Murphy said there was “no information to suggest any connection between Amman and Isis” and that it was not unusual for the terrorist group to claim responsibility for incidents without any involvement. The inquest continues.
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