Protesters from PETA doused themselves in black slime to highlight 'hazardous waste' in the leather industry, while Extinction Rebellion used a 'bleeding' red carpet to represent the industry's impact on the climate.
London Fashion Week opened on Friday with catwalk controversy as it was targeted by two separate protests.
Representatives of animal charity People for the Ethical Treatment of Animals (PETA) doused themselves in black slime to highlight what they called "hazardous waste associated with the leather industry".
Meanwhile, climate activists Extinction Rebellion used a "bleeding" red carpet to draw attention to the clothing industry's impact on the environment.
"[We] are calling for the fashion industry to tell the truth about its contribution to the climate and ecological crisis," the group said in a phone message to journalists.
At a time of growing public environmental awareness, fashion brands are being urged to be more sustainable and cut waste.
Caroline Rush, chief executive of the British Fashion Council, which organises London Fashion Week, said: "Extinction Rebellion asked us to cancel London Fashion Week [as] a grand statement of what the industry needs to do.
"But that doesn't solve the problem in terms of the way the industry needs to address the climate change emergency, and actually platforms like London Fashion Week bring businesses and the industry together to engage in the conversation and it allows us the opportunity to really drive forward the agendas."
London Fashion Week is the second leg of a month-long catwalk season that also includes New York, Milan and Paris.