A spokesperson for the Community Security Trust said: “This latest terrorist attack shows, yet again, how such things can happen in any public place.
"People need to consider how they themselves would react if caught up in such a situation: how they would get away, hide, or even fight back if they had to.”
Amman was jailed in December 2018 for possessing and disseminating recognised terrorism-related documents. He was sentenced to three years, four months but was released early at the end of last month.
On Monday, Prime Minister Boris Johnson said he had “come to the end of my patience” on the automatic early release of people convicted of terrorism offences and said he would “take action”.
He said the Government would look at how to “retrospectively” apply any changes to early release to existing prisoners serving their sentence, not just those convicted after any change.
