Cornish separatists have threatened to attack restaurants owned by Jamie Oliver and Rick Stein in an attempt to drive out English “incomers”.

In a statement sent to a local newspaper, the little-known Cornish National Liberation Army threatened to firebomb the celebrity chefs’ businesses in retaliation for them “alienating” local people.

The e-mail claims that the group has substantial funding and promises to continue its campaign to remove the “imperialist English flag of St George” from Cornwall.

A spokesman for Devon and Cornwall Police said that the force was taking the threats very seriously. He said: “We will vigorously investigate any premeditated or publicised planned criminal activity.”

The group says that its top target is “Padstow (Padstein) and Rick Stein Operated Businesses”. The e-mail says: “It is common knowledge that Rick Stein and his businesses are held in contempt by many Cornish nationals who live in the Padstow area and we [are] currently seeing Stein riding over local democracy. At a unspecified date, Rick Stein will himself feel a ‘rosy glow’ in our Cornish port of Padstow . . . His vehicles and those of his clients are bona fida [sic] targets for our activists.”

Oliver’s Fifteen restaurant in Watergate Bay, near Newquay, is also a target. The message says the chef is: “Another incomer who has caused the inflation of house and other living costs at Cornish expense and subsidised by European funding who, together with his clients and customers and the owners of the hotel, are also targets of the CNLA.”

The group claims to be a conglomeration of the Cornish Liberation Army and An Gof, a separatist movement linked to the bombing of a court in St Austell in 1980. The message, signed “CNLA Directing Council”, claims the group has expertise from Welsh activists who burned English holiday homes in the 1980s, and funding from the US.

It says direct action is necessary to gain home rule for Cornwall. “We respect the work of many moderate Cornish nationals to achieve home rule and a respectful acknowledgement of Cornish history and culture and those who work towards the provision of affordable housing in our Country.

“However, we feel that the message is being lost by untrustworthy politicians who fail to recognise the gathering strength of feeling in this Country currently dominated by the Westminster Parliament and its cronies.”

Politicians in Cornwall condemned the threats. David Whalley, leader of Cornwall County Council, said: “These people are not working in the best interests of the people in Cornwall. In fact, this is unacceptable behaviour. I understand there may be frustrations about not being able to get affordable housing, but this is not the way to achieve it.”

Dick Cole, leader of Mebyon Kernow, which campaigns for greater self-government for Cornwall, said: “I am saddened that we seem to have a handful of people running around Cornwall masquerading as some pseudo-terrorist group, threatening business and their customers. Such actions have no place in modern Cornwall. What they are saying is wrong and objectionable.”

A spokesman for Fifteen said: “We are very surprised and disappointed by the statement because everything about us is Cornish. We are a fifth-generation Cornish business employing large numbers of Cornish staff.”

Stein refused to comment.

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