The prime minister and home secretary have condemned an incident in which a senior BBC journalist was angrily confronted and pursued by anti-lockdown protesters as “disgraceful” and “appalling”. Police interviewed one man on Tuesday and were seeking a second after footage circulating online showed Nick Watt, the political editor of BBC Newsnight, being followed on a street near parliament on Monday by unmasked protesters who shouted into his face. Watt, who was wearing a BBC lanyard, then doubled back through police lines as people shouted “traitor” and other slurs at him. An investigation has been launched by the Metropolitan police, which said a number of possible offences had been identified after the footage was reviewed. The BBC said in a statement on Tuesday: “This behaviour is completely unacceptable. All journalists should be able to carry out their work without intimidation or impediment.” Boris Johnson tweeted: “Disgraceful to see the hounding of Nick Watt doing his job. The media must be able to report the facts without fear or favour – they are the lifeblood of our democracy.” The home secretary, Priti Patel, said on Twitter: “The video of BBC Newsnight’s Nick Watt being abused by a mob is appalling and distressing. This behaviour is never acceptable.” “The safety of journalists is fundamental to our democracy,” added Patel, who said the government had this month launched a consultation to understand better the nature and volume of threats and abuse against journalists operating in the UK. The National Union of Journalists (NUJ) said it had raised the incident with the Met and asked the force to review its response. Criticism was directed at the apparent inaction of police officers who are seen standing by in the footage as Watt is pursued. Michelle Stanistreet, the general secretary of the National Union of Journalists (NUJ), said: “The hounding and abuse levelled at Newsnight’s Nick Watt outside Downing Street yesterday by anti-lockdown protesters was frightening and outrageous. “It is genuinely shocking that a man escaping a mob screaming at him, shouting traitor and calling him scum, didn’t result in the police immediately intervening. Action should be taken against these thugs. No one should have to tolerate such abusive behaviour and harassment simply for doing their job.” The Met drew further criticism after initially saying “officers were not in the immediate vicinity of the incident” – a statement which it later said had been drafted after viewing a 45-second clip which had circulated online. On the basis of a longer clip, the force said it was clear the incident began on Whitehall where officers were present. “The behaviour shown in the video is unacceptable. Members of the public, of any profession, have the right to go about their day without being subjected to verbal harassment or actions that put them in fear for their safety,” said the force. The incident was also condemned by Jo Stevens, the shadow culture secretary, who said: “This extremely disturbing footage showing clear intimidation of a journalist while carrying out his job is absolutely unacceptable and should be condemned in the strongest terms.” Watt had been filming in the area earlier for a segment on Newsnight, which was covering the extension of England’s lockdown. The footage of Watt being harassed was broadcast by anti-lockdown activists behind their own YouTube channel. The incident is the latest to raise concerns in recent times about intimidation and harassment of journalists. Others have spoken of a particular hostility among anti-lockdown activists “What happened to Nick Watt is far from an isolated incident, as many news reporters will confirm,” tweeted Robyn Vinter, an investigative journalist based in Leeds. “I was at a job only a few weeks ago where broadcasters were harassed by aggressive anti-lockdowners (though on a smaller scale). BBC journalists kindly shared their security with me.” Others who condemned the incident included the Labour MP David Lammy who tweeted: “Absolutely horrific. Solidarity with Nick Watt. It is a fundamental principle of any democracy that journalists are free to do their jobs without intimidation.”