London UFO crash

The London UFO crash was the name BBC News gave to an incident in March 2006 which saw the destruction of Big Ben at the hands of a UFO which seemingly crashed into the River Thames in central London. (TV: Aliens of London/World War Three)

Elton Pope, while shopping for a suit, was among the bystanders that witnessed the crash in London. He initially mistook the ship for a plane. (TV: Love & Monsters)

Legacy
Repair work on Big Ben lasted as late as Christmas 2006. (TV: The Christmas Invasion)

Whilst listing beings they had encountered in their travels with the Doctor, Rose cited "Slitheen in Downing Street" to Sarah Jane Smith. (TV: School Reunion) This would later be recalled by Sarah Jane whilst she was facing Slitheen who used Coldfire Construction in a bid to drain the Sun's energy. These Slitheen admitted that they enacted this scheme on Earth in retaliation for the loss of their family, in what they described as "just a routine job". Upon hearing this, Sarah Jane suspected that she knew what or "Who happened." (TV: Revenge of the Slitheen)

Following his election in 2008, British Prime Minister "Harold Saxon", actually, cited the destruction of Big Ben as an example of an alien event which the British government failed to disclose to the public. (TV: The Sounds of Drums)

Parallel universes
In a parallel universe, Rose Tyler found that no spaceship crashed into Big Ben. (AUDIO: The Endless Night) She later determined that the ship did not appear in at least one other universe. (AUDIO: The Last Party on Earth)