By Paul Burnell
BBC File on 4
Mariyam Manike has no doubt who she blames for the violent death in prison of her son Eevan Nasseem.
Adam Zahir has two homes in the UK
"There was a sheet covering the body of my son. I thought I would pull the sheet, my instinct was to pull the sheet and I could see he was covered with bruises. I realised that my son had been killed.
"Adam Zahir has to take the blame for anything that has happened to me. My whole life is ruined," she told BBC File on 4. "He received reports that torture was going on in the prison and nobody had done anything and the people who tortured him were under his command."
Adam Zahir was chief of police until last year, in the Maldives, where he was in charge of a department accused of human rights abuses such as political imprisonments and torture.
Mr Zahir has homes in Lancashire and London, much to the distress of those who allege they suffered at the hands of the police.
Last November, elections in the Maldives saw the end of a regime described as one of the world's most repressive by human rights groups.
Mrs Manike has a civil action in the Maldives against the country's defence ministry and wants Mr Zahir to give evidence, but she also wants Britain to act because of his UK links.
This is a matter of conscience, the conscience of good people who do not want to see dictators and human rights abusers living in their neighbourhoods.
Mohamed Waheed, vice-president Maldives
Her views are echoed by the country's new vice-president Mohamed Waheed, who told the BBC: "He should face justice even if he is here, and with the British Government being such a strong advocate of human rights, it is only natural the British Government should look into this.
"This is a matter of conscience, the conscience of good people who do not want to see dictators and human rights abusers living in their neighbourhoods."
Mr Zahir was not available for comment.
The British Government said in 2002 it was determined the UK will not harbour war criminals or people who commit other human rights abuses abroad.
But File on 4 has learned that several hundred could be here, many with government knowledge.
If the War Crimes Team of the government's UK Border Agency believes a person applying to enter the UK was involved in crimes against humanity, war crimes or genocide, it can recommend refusal
Figures released to File on 4 under the Freedom of Information Act show that the team recommended in the past five years that 350 should not be allowed to enter the UK.
Decisions were taken to exclude 146.
The FOI figures do not include people who entered the UK illegally or changed their names.
The government said some applicants had to stay, despite their alleged crimes, because deportation would have breached the European Convention on Human Rights.
Only one case has ever come to court, an Afghan warlord accused of torture and kidnapping.
Few cases are investigated and human rights groups claim that police investigations are often dropped because of the lack of resources as allegations of these crimes are usually investigated by the Metropolitan Police's counter terror unit whose officers can be redeployed at short notice.
But in the case of Adam Zahir, the Metropolitan Police took no action and Lancashire Police had never heard of him even though there had been demonstrations outside his house near Preston.
Lord Carlile, who is the government's reviewer of anti-terror legislation, believes more police resources are needed.
Adam Zahir's home in Lancashire
"I would hope the new Metropolitan Police Commissioner would think it right to set up an additional unit, to investigate international criminal matters of this kind," he told File on 4.
And he is backed by Sir Ken MacDonald, the former Director of Public Prosecutions: "It's a question of the government's priorities and political will, how seriously do people take the need to go after people who commit the worst crimes that can be committed, mass murder, attempts to wipe out a whole population?"
The Home Office told the BBC: "It is the government's policy that the UK should not be a safe haven for war criminals."
It added: "There are very real evidential and jurisdictional difficulties in pursuing such cases through the criminal justice system where the offences have been committed abroad and in many cases several years ago.
"Using immigration powers enables us to prevent suspected war criminals coming to the UK, to refuse them asylum or immigration status and where possible to seek their removal."