The suspect in the attack on Sunday on a Dover immigration centre was a pensioner from Buckinghamshire, police have revealed, as questions grew over why the incident was not being treated as a potentially terrorist incident. Kent police are leading the investigation, which follows petrol bombs being thrown at a migrant centre by a man in a car, and then shortly afterwards the body of a man being found at a petrol station. Police said the man found dead was a a 66-year-old from High Wycombe, Buckinghamshire, 115 miles from Dover. A property in High Wycombe was being searched on Monday as the investigation continued. Photographs of the suspected attack showed a man releasing a plastic bottle taped to a lit firework on Dover harbour’s Western Jet Foil, where Border Force officers process people who have crossed the Channel in small boats. The suspect was confirmed dead shortly after the incident. Kent police said they were keeping an open mind on the motive for his actions, but that they were not treating it as a terror attack. Neither Kent police nor counter-terrorism police who cover the south-east have publicly explained whether counter-terrorism investigators have helped the investigation. Both specialist counter-terrorism officers and MI5, the security service which leads on intelligence about far-right terrorism, are believed to have been monitoring developments. For an act of violence to be treated as potential terrorism there needs to be a belief that it may have been politically or ideologically motivated. Speaking in the Commons, the shadow home secretary, Yvette Cooper, asked whether counter-terrorist officers were investigating the incident. “It does not make sense for them not to be,” she said. Edward Biggs, a Labour town councillor whose ward includes the immigration centre, urged the police to treat the attack as terrorism. He said: “I don’t see how they can’t treat it as a terrorist incident. It may not be a terrorist cell. I’m aware there are factions around Dover and in Kent who could and will join in this. So the police should definitely be treating this as terrorist incident.” The anti-fascist charity Hope Not Hate said it had recorded 165 incidents of activity from far-right and anti-refugee activists at immigration facilities so far this year. It said the government’s “demonisation” of asylum seekers and refugees was “mainstreaming anti-migrant rhetoric and encouraging far-right groups to target” these people. Rosie Carter, the director of policy at Hope Not Hate, said: “The terrible incident at Dover does not stand in isolation. “It is the result of repeated demonisation and scapegoating of migrants, asylum seekers and refugees by the government and by the media. This rhetoric shapes hostile public opinion and encourages the far right at a time when violent extremism is at a high. “We have warned the government time and time again that their failure to provide suitable community-based accommodation while ramping up hostile language and fuelling enmity and division with an inhumane and unworkable system would have dangerous consequences that we have seen before. “The government continues to bang the immigration drum, employing dehumanising language and scare tactics to feed a narrative that conflates migration with criminality and terrorism, continually winding up the issue by repeatedly blaming a ‘broken’ asylum system. “Cracking down harder does not fix a system that traps people seeking refuge in destitution, keeps families apart for years and wrongly deports people, but it does stir up immigration as a political issue. And that plays straight into the hands of the far right.” Biggs said there was a concern in Dover that the immigration centre on the harbour had become a “target for extremists”. He said: “We’ve had demonstrations from different factions who have nothing to do with how Dover feels about migrants and treating people fairly.” Biggs also urged ministers to stop demonising people who cross the Channel in small boats. “They just hype it up,” he said. “The home secretary’s rhetoric is more and more aggressive towards migrants, when there should be safe passage for migrants. “It is not a surprise to us that there has been an incident, because some of the narrative that has been out there has been very damaging.” He cited a news story about people sleeping with sledgehammers under their beds because of fear of refugees on the Kent coast. “It has just got completely out of control,” Biggs said. “The Rwanda rhetoric and all this stuff about bring the navy and pushing boats back is clearly the wrong policy. It hasn’t worked. “We need to look at a more compassionate way. Look at the different way we approach Ukraine migrants and Channel migrants. Why is it so different?” The Labour MPs Nadia Whittome and Diane Abbott also linked the Dover attack to government rhetoric. Abbott tweeted: “Disgraceful scenes. This is where the demonisation of asylum seekers and their mistreatment leads.” Whittome tweeted: “Let’s be clear: migrants are not to blame for acts of violence against them. Fear, hate and dehumanisation are.” The former Ukip leader, Nigel Farage, who has continued to play on fears about Channel crossings in regular video updates, blamed the Dover attack on a “complete and utter lunatic”. In a video, he said: “The guy was a lunatic. He is not representative of those of us that want to have a proper debate. “I will not be bullied by the forces of political correctness, I will not be bullied by the hard left from letting this debate and letting this conversation go.”