The campaign group Black Lives Matter say their activists are responsible, positing a link on their Facebook page with pictures of the demonstration with the line: "London City Airport is #Shutdown to protest the UK's environmental impact on black people."
A photograph circulating on Twitter showed the protesters surrounded by police and lying under a wooden tripod. They had erected two large posters with the slogans "Black Lives Matter" and "Climate Crisis is a Racist Crisis".
The British arm of the group, which started in the United States as a reaction to fatal shootings of black people by white U.S. police officers, said it wanted to highlight Britain's environmental impact on the lives of black people locally and globally.
"Black people are the first to die, not the first to fly, in this racist climate crisis," the group said in a statement.
"When black people in Britain are 28 percent more likely to be exposed to air pollution than their white counterparts, we know that environmental inequality is a racist crisis."
The campaign group, which blocked a main road to London's Heathrow Airport in August, said City airport was designed for the wealthy while those who lived near the site struggled on low salaries.
The Met Police has issued the following statement:
"At 05:40hrs on Tuesday, 6 September, officers were alerted to a number of protesters who had made their way airside at London City Airport.
Nine people erected a tripod and locked themselves together on the runway.
Officers negotiated with the protestors and specialist officers arrived to 'unlock' the protestors.
At approximately 09:30hrs officers started to arrest the protestors. So far seven people have been arrested on suspicion of:
= aggravated trespass
= being unlawfully airside
= breaching London City Airport bylaws
They have been taken to east London police stations.
Two people remain locked together on the runway."
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