Deputy Assistant Commissioner Martin Hewitt, of the Metropolitan Police, says there remains "gaps in understanding" regarding the death of MI6 worker Gareth Williams.
But he has concluded, following two years of investigation, that it is "most probable" that the codebreaker was alone at the time of his death.
More top news
A documentary about the brutal gang rape and murder of a woman on a Delhi bus in 2012 has been banned in India.
Scotland Yard are asking for the public's help to find the dangerous men who are wanted in Europe but are believed to be hiding in the UK.
A Bolton chemistry teacher is to be sentenced today after admitting terror offences - with police claiming he wanted to join Islamic State.