Newsprinters said overnight that some papers would be late to the shelves on Saturday as work at their Broxbourne, Knowsley and Motherwell sites was disrupted by climate activists in a protest that has drawn criticism from both government and opposition ministers.
Police said 30 arrests had been made so far and more were expected as over 100 Extinction Rebellion protesters blocked roads outside the presses with vehicles and bamboo structures over Friday night.
Delivery lorries had not left the Broxbourne site as of 6am on Saturday, Hertfordshire Police reported while Merseyside Police said protesters were still present in the morning.
Police arrested 17 people at Knowsley and 13 at Broxbourne, where assistant chief constable Owen Weatherill said more arrests were anticipated.
A smaller protest was held at a site in Motherwell where The Scottish Sun is printed.
Extinction Rebellion said they were planning to block routes out of the printworks where Murdoch titles including The Sun, The Times and their Sunday sister-titles are printed along with the Daily Mail, the Daily Telegraph and the Financial Times.
"Coverage in many of the newspapers printed here is polluting national debate on climate change, immigration policy, the rights and treatment of minority groups, and on dozens of other issues," the group said.
A spokesperson for Newsprinters apologised to readers of the affected titles and called the protests "an attack on the free press".
"Overnight print workers, delivery drivers, wholesale workers and retail newsagents have faced delays and financial penalty. This is a matter for the police and the Home Office," the spokesperson said.
The Sun, which was the UK's highest-selling daily newspaper for more than 40 years until it was recently overtaken by the Daily Mail, apologised to readers in a statement, where they claimed the protests were "an attack on all the free press".
On Saturday morning, government and opposition ministers voiced their disapproval of the protests.
Priti Patel, the home secretary, said: “This attack on our free press, society and democracy is completely unacceptable."
Robert Jenrick, the communities secretary, said: “A good day to #buyanewspaper. A free press matters to all of us who value a free society. They mustn't be silenced by an intolerant minority."
Labour's shadow international trade secretary Emily Thornberry told Times Radio on Saturday morning: “This is very worrying and I don't really know what it is that is expected to be achieved and I know that for many older listeners it's very much part of their daily life, getting their paper delivered in the morning, and I just think it's wrong.”
Dawn Butler, MP for Brent Central who served as shadow equalities secretary under Jeremy Corbyn, however praised the activists, tweeting: "Bravo".
The climate activist group has staged demonstrations in London in recent days where protesters glued themselves to the ground outside the Houses of Parliament and blocking traffic on nearby Lambeth Bridge.
More than 500 people were arrested during the protests, 200 of which were linked to the Lambeth Bridge incident, Metropolitan Police said.
The force said risk assessments provided by Extinction Rebellion to explain how they were minimising the risk of coronavirus transmission were "unfit" and restrictions have been put in place targeting a protest planned for Saturday.
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