London City Airport travelers were met with delays Tuesday as flights were temporarily stopped because of a Black Lives Matter protest. After creating a tripod, nine activist “locked themselves together” on the runway, BBC News reported.

Black Lives Matter activists in the United Kingdom took responsibility for the protest aimed at bringing attention to Britain's "environmental impact on the lives of black people locally and globally," the social justice movement said. The activists were arrested on suspicion of aggravated trespass and breaching London City Airport bylaws, CNN reported. 

London City Airport is the fifth busiest airport in the London region, popular among corporate travelers because of its proximity to Canary Wharf and the City of London, which house the British capital's two financial centers. In 2015, 4.3 million passengers used the airport.

The Black Lives Matter UK movement decided to protest the airport because of its plans to expand, a move that would reportedly negatively affect one of London’s most poverty-stricken areas. The organization tweeted, “Climate crisis is a racist crisis.”

"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," a statement from the group said. "Black people are the first to die, not the first to fly, in this racist climate crisis. We note, however, that the UK is willing to charter special flights to remove black people from the country based on their immigration status."

The Scotland Yard Metropolitan Police service is reportedly investigating how the protesters were able to get onto the runway. One theory is that they may have swam across the River Thames or used a boat.

During the protest, passengers were offered refunds for canceled flights and refreshment vouchers. Inbound flights were diverted to other airports.

The Black Lives Matter movement was started in 2012 after George Zimmerman, a white man in Florida, was found not guilty of killing African American teenager Trayvon Martin.