Lord Ian Blair, the former Metropolitan Police commissioner, has died at the age of 72.
The crossbench peer led Britain’s largest force between 2005 and 2008, including during the 7/7 terrorist attacks.
Christ Church, Oxford, where he studied English and later became an honorary student, confirmed his death on Friday evening.
Born in Chester in 1953, Lord Blair joined Scotland Yard’s graduate scheme in 1974.
He rose through the ranks and went on to lead major investigations, including the response to the 1987 King’s Cross fire caused by a wooden escalator.
In 1998, he became chief constable of Surrey Police before returning to the capital two years later as the force’s deputy commissioner.
He was appointed commissioner in February 2005, just five months before 52 people were killed in a series of suicide bombs on the city’s transport network.
Around that time, Blair he claimed Islamic terrorism "is a far graver threat in terms of civilians than either the Cold War or the Second World War".
Two weeks later, firearms officers killed Jean Charles de Menezes at Stockwell station, after mistaking him for a terror suspect.
Within hours of the tragedy, he called the Home Office in an attempt to block an inquiry into the killing.
The Met was later fined after an Old Bailey jury found it had breached health and safety rules and failed in its duty to protect members of the public in the shooting of the innocent Brazilian.
Lord Ian Blair was cleared of wrongdoing, although he faced pressure over the incident for the remainder of his leadership.
He was also reprimanded for recording telephone conversations with the then-Attorney General Lord Goldsmith and three police watchdog officials.
His last months in office were mired in controversy after he was accused of racism by ethnic minority officers, including then-assistant commissioner Tarique Ghaffur.
He was forced to resign in October 2008 after a bitter showdown with then-mayor of London Boris Johnson, who said he had no confidence in him.
Ghaffur signed a gagging clause as part of a settlement agreement, but was said to have received a £300,000 compensation deal.
In his resignation letter, Lord Ian Blair said: "It is the duty of the commissioner to lead the Met through good times and bad: To accept the burdens and pressures of office and, above all, to be a steward of the service he commands."
He was elevated to the House of Lords by then-prime minister Gordon Brown in 2010, serving in the Upper House until his death.
Lord Blair married, in 1980, Felicity White, with whom he had a son and a daughter.
Christ Church, Oxford said in a statement: “The Christ Church community would like to extend its condolences to the family of Ian Blair, The Lord Blair of Boughton QPM, who has died at the age of 72.”
