The mother of London terrorist Sudesh Amman has described him as a "nice, polite boy", who was radicalised while in high security jail and by viewing extremist material online.
Police have named Amman, 20, as the attacker.
He was killed on a street in the south London district of Streatham yesterday afternoon by armed officers after he had grabbed a knife from a shop and attacked two bystanders.
Scotland Yard said armed officers were following Amman on foot as part of a "proactive counter-terrorism surveillance operation" in Streatham High Road.
The three victims were taken by ambulance to south London hospitals.
One man, in his 40s, is no longer considered to be in a life-threatening condition following treatment, police said.
A woman, in her 50s, who had non-life threatening injuries has been discharged from hospital.
Police said a second woman, in her 20s, who suffered minor injuries believed to have been caused by glass following the discharge of a police firearm, continues to receive treatment.
Haleema Faraz Khan told Sky News that her son, who had wanted to study biomedical science, had seemed "normal" when she visited him last Thursday.
The 20-year-old, who was jailed for possessing and distributing terrorist documents in December 2018, had recently been freed from prison and had been staying at a bail hostel for the past two weeks.
His mother told the broadcaster she believed he had been radicalised while in high security jail Belmarsh and had also developed extreme views after looking at Islamist material online.
The atrocity follows the attack at Fishmongers' Hall in the City of London in November, when another convicted terrorist, Usman Khan, murdered two people despite being on probation.
Cambridge graduates Jack Merritt, 25, and Saskia Jones, 23, were stabbed to death at a rehabilitation conference.
Meanwhile Justice Secretary Robert Buckland has promised to introduce "emergency legislation" to end the current arrangement whereby terrorist offenders are released automatically after they have served half of their sentence.
