London: As the sun went down over the British capital, Royal Marine Martyn Williams abseiled from a helicopter hovering over the River Thames, carrying the Olympic flame to the ground in a lantern hanging from his belt.
The action film-style descent at the historic Tower of London began symbolically at 20:12 pm (1912 GMT), exactly seven days before the opening ceremony on July 27.
Williams, 23, who was injured in Afghanistan in 2008 but is now fit again, passed the flame to British athlete Kelly Holmes. The winner of the 800 metres and 1,500m at the 2004 Athens Olympics then used the lantern to light the Olympic torch.
The flame will spend the night in the Tower of London, where Queen Elizabeth II keeps her ceremonial jewels, before embarking on a seven-day tour of the capital.
The tour will be the culmination of an 8,000-mile (12,800-kilometre) relay around Britain and the Republic of Ireland.
London Olympic chairman Sebastian Coe said he was "delighted" to welcome the flame, adding: "It's made an extraordinary journey."
Mayor of London Boris Johnson said: "Tonight London becomes the first city in history to be entrusted three times with the sacred flame of the Olympics first kindled by the ancient Greeks.
"It will spread the crackling bush fire of Olympic enthusiasm throughout this city and this country.
"I pledge that we will keep that flame burning brightly."
Earlier Friday, before the flame reached the capital, police arrested a 17-year-old man after he tried to grab the torch from a female torchbearer while it passed through Gravesend, a town southeast of London.
The teenager sprinted out of the crowd toward the torchbearer and was grabbed by the security officers accompanying the torch.
The torch will begin its tour of the capital in Greenwich on Saturday and will travel through every London borough, carried by 982 torchbearers, in the coming week.