Sudesh Amman, the accused of killing and injuring people on Sunday in London with a knife, was an extremist in his thoughts. He was jailed in 2018 for terrorism but released halfway through serving his three-year sentence.
Amman was jailed jailed for promoting violent material. He even encouraged his girlfriend to behead her parents. He was under surveillance at the time of the attack.
In November 2018, he pleaded guilty to possession of terrorist material including documents and disseminating terrorist publications. The following month he was sentenced to more than three years in prison.
According to authorities, Amman , when began committing terrorism offences for the first time, was just 17 and living at home with his mother and younger siblings.
Police got clue of his activities in April 2018 and he was arrested by armed officers in a north London street a month later. When officers examined his computers and phone, they found he had downloaded material about making explosives and carrying out terrorist attacks.
According to messages found in his phone, Amman had extreme views and those views he had discussed with his family, friends and girlfriend. He had also discussed his desire to carry out an attack, often focused on using a knife.
In December 2017, Amman posted a picture of Islamic State leader Abu Bakr al-Baghdadi, who was killed during a US raid in Syria in October, and told his brother in a message that "the Islamic State is here to stay."
He also described Yazidi women as slaves, and in another message he encouraged his girlfriend to behead her parents.
Police said he had shared an online Al-Qaeda magazine with his family and while in a discussion about school with a sibling he wrote he would "rather blow myself up."