An LBC journalist says she was handcuffed during her reporting on the M25 disruption by protesters.
A broadcast journalist reporting on a climate protest should not have been arrested, police have said.
LBC reporter Charlotte Lynch said she was arrested on suspicion of conspiracy to commit a public nuisance during her reporting about the M25 on Tuesday and was held in custody for five hours.
Hertfordshire Police said “in retrospect an arrest would not have been necessary”.
Ms Lynch said the force had not contacted her directly to apologise.
She called the incident “absolutely terrifying”.
Ms Lynch said she was arrested on a road bridge between junction 20 (Abbots Langley) and junction 21 (M1/St Albans interchange) during Tuesday’s protest by the Just Stop Oil group.
She said she showed officers her press card and explained she was reporting on the demonstration, but was handcuffed, searched and taken to Stevenage police station in a custody van.
The incident came after a photographer and a filmmaker said they were held in police custody for about 13 hours on Monday after being arrested by Hertfordshire officers.
Hertfordshire Police chief constable Charlie Hall said the force’s officers had “been instructed to act as quickly as they can, using their professional judgement, to clear any possible protesters”, but he “recognised the concerns over freedom of the press”.
“Officers have been instructed to ensure they conduct full and thorough checks before making an arrest decision, as well as getting a final approval by a supervisor before making any arrests of anyone who is identifying themselves as press,” he said.
“Further guidance on dealing with the press has been reiterated to officers during briefings.”
He added that Hertfordshire Police had made a request for another force to independently investigate its approach to the protests and “identify any learning we should take in managing these challenging situations”.
“In advance of this, with regards to the arrest of the LBC journalist, the circumstances of the arrest have been internally reviewed,” he said.
“Though the actions of the officers at the scene are understandable, in retrospect an arrest would not have been necessary.”
Ms Lynch said: “I haven’t been contacted by anybody from Hertfordshire Constabulary to apologise to me and to confirm that I will be de-arrested and my DNA removed from their records.”
David Lloyd, the Conservative police and crime commissioner for the county, said the media needed to “reflect on how [it was] reporting” the protests.
Speaking to BBC Three Counties Radio, he said: “The reason that Just Stop Oil are continuing to do this is that they know they will get publicity if they do it.
“Frankly, [the protestors] have got exactly what they want by having front page news using their name every single day.
“One thing that the journalistic community could do, through their editorial policy – and I very much believe in a free press – but we do need to think about whether or not we’re adding flames to the fire by having these sorts of discussions.”
He added that “ordinary people’s lives are being held to ransom” by the protesters and “frankly we’re all fed up to the back teeth of it”.
The National Union of Journalists’ (NUJ) general secretary, Michelle Stanistreet, said: “The commissioner’s apparent desire to influence editorial lines instead of recognising the work of journalists as fundamental to upholding a free press is of grave concern.
“Shifting blame on to editors publishing content that is clearly in the public interest fails to recognise the severity of recent incidents and their wider impact on the public’s right to stay informed.”
Thursday has seen a fourth consecutive day of protests taking place around the London orbital motorway.
Just Stop Oil said it was calling for the government to end the country’s use of fossil fuels, to invest in renewable energy and for better building insulation.
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