Flights were suspended at London City Airport after nine protesters locked themselves together on the runway and erected a tripod, London's Metropolitan Police said in a statement.
Black Lives Matter UK, a network of anti-racism activists, said in a statement that the action was taken to protest Britain's "environmental impact on the lives of black people locally and globally."
The police said the protesters were arrested on suspicion of aggravated trespass, being unlawfully airside and breaching London City Airport bylaws, and were taken into custody. The statement was issued nearly six hours after police were alerted of the protest.
London City Airport tweeted that the runway has since reopened, and it advised passengers to check with their airlines for flight information.
Protest cites 'racist climate crisis'
London City Airport, the fifth busiest airport in the London region, is popular with corporate travelers due to its proximity to Canary Wharf and the City of London, the British capital's two financial centers.
Black Lives Matter UK said the centrally located airport was planning to expand its capacity, which would negatively affect the surrounding community in one of London's most deprived areas.
The group's statement said the UK's impact on the environment was global, with "7 out of 10 of the countries most affected by climate change ... in sub-Saharan Africa." Climate change, it said, was creating huge numbers of climate refugees.
"Whilst at London City Airport a small elite is able to fly, in 2016 alone 3,176 migrants are known to have died or gone missing in the Mediterranean, fleeing conditions that they did not create because cheaper, easier and most importantly safer avenues have been blocked by the UK and other European countries," the statement said.
"Black people are the first to die, not the first to fly, in this racist climate crisis."
An image tweeted from the Black Lives Matter UK account showed the protesters on the runway, alongside banners saying "Black Lives Matter" and "Climate Crisis Is a Racist Crisis."
'Why deviate the BLM cause?'
The conflation of the Black Lives Matter and environmentalist causes -- and the suggestion that the airport was for the "elite" -- prompted a number of Twitter users to express confusion over the protest.
"There are bigger, more respected & better funded charities that protest climate change," one Twitter user wrote.
"Why deviate the BLM cause to jump on that bandwagon?"
Responding to questions on social media about whether the protest was a Black Lives Matter action, given the environmentalist cause and the fact the nine protesters were white, the Black Lives Matter UK Twitter account posted that the movement "is and always has been black led."
"There's a need for white people to take responsibility in a society that privileges them through racism and anti-black racism in particular," it tweeted.
"Today's protest is an example of white allyship under black leadership."
Heathrow targeted previously
Last month, Black Lives Matter UK protesters blocked a main road leading to Britain's largest airport
, Heathrow, bringing traffic to a standstill. Similar actions were carried out in Birmingham and Nottingham in a coordinated day of action.
The British activist network, inspired by the US movement of the same name
, said at the time that the protests were called to mark the fifth anniversary of the fatal police shooting of Mark Duggan
, whose death sparked riots in 2011.