NUJ says arrest of men accused of filming on Menie estate without permission has important implications for press freedom

The National Union of Journalists has protested about the arrest and detention of two documentary film-makers who were investigating complaints about building works at Donald Trump's golf resort near Aberdeen.

Anthony Baxter and Richard Phinney were arrested for breach of the peace, held for four hours, and had their DNA, photographs and fingerprints taken, after the Trump organisation accused them of entering its offices at the site and filming documents without permission.

The two men were arrested as they investigated allegations that contractors working for Trump accidentally cut off the water supply to several local residents, including his fiercest critic Michael Forbes, for several days. The journalists said their camera equipment was held by police for five days, preventing them from filming.

Baxter and Phinney, who have worked for the BBC and Channel 4 News and won awards for their films, strenuously deny the allegations against them. They insist that Trump's local manager, Paul O'Connor, freely agreed to be interviewed on camera and that their film proves they entered the building with permission and never filmed any documents.

In a letter seen by the Guardian, Grampian police said they had given the film-makers written warnings even though there was "sufficient evidence" to report both for breach of the peace.

Paul Holleran, the NUJ's regional organiser in Scotland, said the arrests were unjustified and had important implications for press freedom. A formal letter of complaint has been sent to the Grampian chief constable, Colin McKerracher.

"This is a blatant example of police interference aimed at stopping bona fide journalists from doing their job," Holleran said. "Their footage shows they were asking very pertinent questions in a mannerly fashion as befits professional journalists. I believe this is a breach of human rights, and we are taking legal advice. I think this must be one of the first cases in this country of journalists being arrested for just carrying out interviews to establish the truth and hold people to account."

Grampian police have refused to comment in detail since Baxter appealed.

A spokeswoman said: "Grampian police can confirm a report has been submitted to the procurator fiscal in connection with an incident at the Balmedie estate on 30 July 2010. As the matter is still the subject of active legal proceedings it would be inappropriate to comment further."

Baxter, a former news editor at Capital Radio in London, and a former producer of Radio 4's Face the Facts, said he and Phinney were making a documentary about the impact on residents of Trump's £750m golf resort and about the controversial process to grant Trump planning permission.

George Sorial, Trump's senior representative, confirmed the water was cut off accidentally when contractors broke an old clay water pipe. "The matter was addressed immediately and it was repaired immediately," he said. Sorial insisted the two men "burst" unannounced into Menie House, Trump's home at the resort, and were disruptive He said his organisation had "a right to protect its own people", and added: "I think it's entirely appropriate to call the police. We have a very good relationship with all the media. We genuinely have an open-door policy [but] it's not acceptable to have two people burst into an office unannounced.

Baxter and Phinney were arrested as they were interviewing on camera Susie Munro, a resident who objects to the development of the resort. They say the police asked them to turn off the camera, but they refused.

After Baxter again refused to switch it off, their camera was taken forcibly, they say, and Baxter was handcuffed. All that footage is now likely to be used in the film, they said.

Baxter said the Trump organisation's claims to a local newspaper that he and Phinney had entered Trump's offices at Menie House, filmed documents and a staff member on the phone without permission, and become involved with the protest group Tripping up Trump, were "factually incorrect".

Baxter told the Guardian: "It is alleged we were photographing confidential documents. We certainly didn't and we've the footage to prove it. It was alleged we were members of Tripping up Trump and that's absolutely incorrect.

"We were legitimately carrying out an interview with a member of Mr Trump's workforce at the site, and he participated in that interview, freely exchanging information, over a period of time.

"Basically, I was being prevented from doing my job, and my legitimate duty is to follow events for that film. [As] journalists we should be allowed to carry out our legitimate normal duties."