Brazil has halted work on a World Cup stadium in the southern city of Curitiba after a judge ruled there were safety fears, local authorities said Wednesday. Work on the Arena da Baixada is more than three quarters ready but Parana state magistrate Lorena Colnago called an immediate halt, the regional state prosecutor\'s office confirmed to AFP. \"The judge has taken the decision and the contractors must abide buy it. They have taken this decision in the belief there is a risk to health. There will now be liaison with the firms in this regard,\" a spokeswoman said.   The stadium is scheduled to host four matches at next year\'s World Cup but work had already been falling behind schedule. A visiting FIFA delegation had in late August already drawn attention to fears the stadium might not be ready, prompting the scrapping of plans for a retractable roof, which will now be added after the tournament.    Contractors must now wait on talks scheduled for early Friday with local authorities and face a daily fine of 500,000 reais (USD 220,000) if they do not observe the judge\'s order. The decision came following a ministry of public works report published last week into conditions at the site. The report found that workers were \"at serious risk of being buried, run over and of collision, falling from heights and of being struck by construction material, among other serious risks.\" Colnago called for the \"effective implementation of all protective measures as laid down in the (ministerial) report, on pain of a daily 500,000 reais fine.\" Contractors contacted by AFP did not comment on the order. A spokeswoman for structural engineers Schlaich Bergermann, which is also working on the new stadium in the northern city of Manaus, said the company had completed its part of the refurbishment and was no longer involved in the Curitiba project. The preparations for Brazil\'s first World Cup since 1950 continue to be beset by fears that construction work is lagging behind schedule on several of the 12 venues. Last week, there was controversy after a judge in the Amazon region suggested using Manaus\' stadium as a prisoner processing stadium after the tournament - the city has no top football team capable of filling the 45,000-seater venue after the Cup. FIFA has told the Brazilians all of their venues must be ready by December and that \"there is no plan B.\" The host nation suffered further negative World Cup-related publicity last week when it emerged construction workers involved in the expansion of Sao Paulo\'s international airport were toiling in \"slave-like\" conditions. Source: AFP