Far-right activists are planning to block humanitarian aid to refugees and migrants drowning in the Mediterranean sea.
The anti-immigrant and anti-Muslim group Defend Europe is commissioning the 422-tonne ship Suunta to disrupt vessels rescuing and giving aid to people fleeing conflict and poverty in north Africa and the Middle East.
Often travelling in overcrowded or unsuitable boats, more than 5,000 died trying to cross the Mediterranean last year and 2,000 have died so far this year.
'We are blaming those NGOs for luring people into the sea,' Martin Sellner, a founder of the Austrian branch of the movement, told Vox. 'We think those NGOs need to be stopped.'
The largely young far-right campaigners aim to 'confront' NGO ships and alter their routes, hoping to drain resources and 'disrupt the human trafficking rings by sinking the abandoned boats they leave behind', according to HOPE not hate.
The extreme guerilla activism from the alt-right group echoes tactics used by left-wing groups such as Greenpeace to oppose whaling ships but directed against Muslims and immigrants.
The so-called 'Identitarian' movement began in France in 2002 but has since spread across Europes It described itself as a 'meta-political project' opposing refugees and attacking social and political elites they see as supporting a liberal and left-wing agenda.
The campaign group HOPE not hate is compiling a legal briefing to tackle the project many fear could increase the number of deaths in the Mediterranean.
Chief executive Nick Lowles said: 'With a history of carrying out provocative stunts, these far-right activists – who cloak themselves in an aura of youth and respectability – pose a serious risk to life on the high seas.'
He warned Identitarians are 'a new wolf in sheep's clothing' with far-right beliefs and connections.
'While they have always used controversial and confrontational tactics, the hiring of this ship is emblematic of a dangerous new confidence within the movement,' he said.
'We will monitor their movements, examine all legal options to hold them to account, pressure crowdfunding services providing a platform for their hate, and lobby politicians to take action against these extremists.'