Extinction Rebellion protesters blocked roads leading to two UK printworks owned by Rupert Murdochâ€™s News Corp on Friday evening.
The groupâ€™s members said they would maintain the blockade throughout the night using vehicles and bamboo lock-ons to try to prevent the companyâ€™s papers from reaching newsstands on Saturday.
The action took place in Broxbourne in Hertfordshire and Knowsley in Liverpool. Extinction Rebellion (XR) said about 80 activists were involved.
Hertfordshire police said they were attending a protest at the Broxbourne site. â€œOur officers are engaging with the group, which consists of around 100 people, and we are working to facilitate the rights of both the protesters and those affected by their presence,â€ the force said in a statement.
The printworks produce News Corpâ€™s Sun, Times, Sun on Sunday and Sunday Times. They also print the Telegraph and Mail titles and the Evening Standard.
Photographs posted on social media showed protesters lying in the road and a banner being unfurled that said: â€œFree the truth.â€
The group was also blocking the News Corps printworks near Motherwell to disrupt distribution of the Scottish Sun.
Alanna Byrne, from Extinction Rebellion, said: â€œWe will only tackle the climate and ecological emergency by breaking the traditional impasse of oppositional politics and coming together, despite our differences.
â€œIf we are to sort out this mess weâ€™re in, the mainstream media must stop profiting from clickbait culture that is swimming in misinformation, that makes us hate our neighbours, suspect foreigners and vulnerable groups, and rally the nation into action.â€
Gully Bujak, an XR activist, said: â€œThe climate emergency is an existential threat to humanity. Instead of publishing this on the front page every day as it deserves, much of our media ignores the issue and some actively sow the seeds of climate denial.â€
Extinction Rebellion activists dumped manure outside News Corp offices in Sydney and Brisbane on Friday to protest against the media giantâ€™s coverage of climate change.
A News Corp source defended the companyâ€™s stance on climate, saying that Saturdayâ€™s Sun was carrying an opinion piece by David Attenborough on how to tackle the climate crisis. The company is also moving to scrap all single-use plastic used to wrap its titles.