A radio journalist has spoken of the “terrifying” five hours she endured in a police cell after being arrested while reporting on a Just Stop Oil protest.

Charlotte Lynch, of LBC, had been reporting on the activists from a road bridge over junction 21 of the M25, in Hertfordshire, on Tuesday, for around 45 minutes when she was approached and questioned by two officers.

After showing them a press card and having explained she was reporting on the demonstration, the officers handcuffed her, took her phone and arrested her on conspiracy to commit a public nuisance.

It comes after a photographer and filmmaker said they were held in police custody for around 13 hours for covering a protest staged by the group.

Ms Lynch said she was searched on the side of the road, before officers seized her devices and took her to a police station in a custody van.

She said: “Got to Stevenage police station, that journey took over an hour because of the M25 being closed.

“I was in the back of a police van, handcuffed, my hands were in front of me, handcuffed the entire time, on my own, the two police officers were behind the glass cage.

“That’s when it dawned on me ‘gosh, I could be charged here’ and everything runs through your mind ‘have I actually committed this offence?’ even though I knew I hadn’t.

“We got to the police station and I thought I’ll answer their questions and I’ll be on my way.”

She then told of being taken to a cell and detained for five hours before officers released her with no further action.

They wanted to know how Ms Lynch knew about the protest, she said.

Ms Lynch said: “It was absolutely terrifying being in a cell with a pad for a bed in one corner and a metal toilet in the other.

“I was just doing my job. What’s also terrifying is what this means for press freedom. It was blindingly obvious I was a reporter.”

Documentary maker Rich Felgate and photographer Tom Bowles had been capturing the activists on a footbridge over the M25 near Kings Langley, Hertfordshire, at close to 11am on Monday when they were handcuffed.

The pair, both of whom say they have no affiliation with the group, had their equipment seized and were taken to a police station, despite efforts to show their press cards.

Mr Bowles, 47, from Hackney, east London, told PA he was held until 1.30am, hours after his wife and 14-year-old daughter were woken up as three officers searched their home.

Journalists shouldn’t get arrested for doing their job

Dawn Alford, executive director of the Society of Editors, said: “The Society is deeply concerned by reports this week of a number of journalists being arrested while reporting on protests by the campaign group Just Stop Oil.

“The protests are a source of legitimate public interest and journalists, filmmakers and photographers have a right to attend protests and report on behalf of the public.

“We strongly condemn the arrest of journalists in the course of their work and will be writing to Hertfordshire Police to seek an urgent explanation and seek assurances that its officers respect the rights of journalists and understand that such actions threaten press freedom.”

Former shadow attorney general Baroness Shami Chakrabarti told LBC: “If the police are now going to start arresting journalists for conspiracy to commit a public nuisance – in other words for knowing that a demonstration is about to take place – then they are effectively shutting down the free press, the free media, in this country.

“And that means the public don’t get the opportunity to judge for themselves whether the police have policed a particular demonstration well or badly, or indeed whether the protesters behaved well or badly.

“So this is very, very serious.”

Education Secretary Gillian Keegan also said: “Journalists shouldn’t get arrested for doing their job.”

Conservative MP for Boston and Skegness Matt Warman, said on Twitter: “It’s extremely hard to understand why the police would arrest a journalist. I hope a fuller explanation or an apology is provided very rapidly.”

Hertfordshire Police said: “As always, our priority remains to ensure public safety – we have a responsibility for the health and safety of all those involved and everyone at the scene, including emergency services, members of the public, members of the press and the protesters themselves.

“These operations are very fluid and fast moving, with the potential to cause widespread and sustained disruption, that not only affects Hertfordshire’s stretch of the M25 but also the wider road networks.

“Our officers have been instructed to act as quickly as they can, using their professional judgment, to clear any possible protesters in order to get roads up and running and to prevent anyone from coming to harm.”

Speaking to journalists at a conference in Westminster on Wednesday, chairman of the National Police Chiefs’ Council, Martin Hewitt, said officers are under pressure when dealing with protesters but media should not be prevented from reporting on them.

He said: “There’s an enormous amount of pressure in play around those protest issues for the reasons that you would understand.

“But, of course, there is a right for journalists to go and report on those occasions and that shouldn’t be prevented in any way.”