Forty-five foreign-born criminals convicted of Islamist-inspired offences are reportedly being allowed to remain in the UK after completing their jail terms.
Five of the terrorists were born in Libya, with others from Algeria, Sudan, Somalia and Eritrea, according to analysis of official data by the Henry Jackson Society. Eighteen were known to have links to proscribed groups, including Al Qaeda and ISIS.
The 45 include triple killer Khairi Saadallah, 26, who went on a stabbing rampage in a park in Reading, 104 kilometres west of London, in the summer.
He had been convicted of a string of violent offences including carrying knives but was not deported after his release because it would have breached his human rights, The Telegraph reported.
He carried out his attack little more than two weeks after his release for non-terrorist offences. Saadallah, who admitted three counts of murder and three of attempted murder last week, will be sentenced next month. He had a history of mental illness and came to the UK from Libya in 2012 as an asylum seeker.
He had come to the attention of counter-terrorism officials who decided that he did not pose a danger of carrying out an attack. Security officials investigated him amid fears he might travel to Libya but the claims were found to lack credibility.
Dr Rakib Ehsan, executive director of the Henry Jackson Society and the report's author, told The Telegraph the released convicts represented a "serious risk pool" to UK security.
He said the case of Saadallah "demonstrates how the UK's benevolence and altruism have been to its detriment".
“Even more worrying is the fact that there are foreign convicted terrorists who have been released from prison who are still walking the streets.”