LONDON — A climate change activist has climbed atop a British Airways plane at London City Airport as demonstrations aiming to alert the world to the dangers of climate change enter a fourth day.

Extinction Rebellion identified the activist as a former Paralympic cyclist. A video streamed by the group showed the activist clinging to the fuselage.

British Airways says that customers were booked onto alternative flights to Amsterdam.

In a separate incident, BBC Newsnight political editor Nicholas Watt tweeted that his flight from London to Dublin had been grounded after a protester stood up to deliver a lecture on climate change just as it was to take off.

Activists sought to shut down London City Airport on Thursday as part of their wave of protests worldwide.