Hundreds of Bulgarian nationalists staged a large anti-Roma rally Saturday as political leaders and security chiefs sought to douse tensions after a week of nationwide demonstrations and sporadic violence. The demonstrators, numbering close to 2,000 according to AFP estimates, marched through central Sofia carrying the national flag and chanted nationalist and anti-Roma slogans. Around 15 people were arrested. Several hundred supporters of the far-right Ataka party gathered in front of the presidential palace in T-shirts that read "I don't want to live in a Gypsy state" and with a banner saying "Gypsy criminality is a danger to the state." Party leader Volen Siderov, who is running for president on October 23, called for the death penalty to be brought back, for Roma "ghettos to be dismantled" and for the formation of militias. The protest came as the prime minister and president, Boyko Borisov and Georgy Parvanov, convened a meeting of the national security council to discuss ways of reducing tensions. Parvanov after the talks called on the media and politicians to "put an end to the language of hatred pushed to the extreme" and vowed that the government would probe the finances of people who lived "a life of luxury." The latest unrest was originally sparked by the killing a week ago of a youth hit by a van driven by relatives of "King Kiro", a Roma clan boss in the southern village of Katunitsa. After locals and people from the surrounding area went on the rampage on Sunday, rallies with anti-minority and even Nazi slogans have taken place across the southern European country on a nightly basis. Police have this week briefly detained several hundred nationalist demonstrators, many armed with knives and batons, who chanted racist slogans and tried to infiltrate Roma areas, notably in Varna in the east. Planned peaceful "Roma Pride" marches this weekend were called off for fear of violence, although young Roma and non-Roma on Saturday handed out flowers to passers-by to express their desire for closer integration. Bulgaria's 700,000-strong Roma minority, nine percent of the population, lives mostly in depressed areas with even higher rates of poverty and unemployment and lower levels of education than the national average. Public frustration against corruption, a yawning gap between rich and poor and the weakness of the justice system, has helped to turn people against them, as well as against Bulgaria's Turkish minority, experts say. What hasn't helped is that many figures like "King Kiro" throughout the ex-communist country are seen by many people as being outside the law. A hoped-for improvement since Hungary joined the European Union in 2007 in tackling corruption and improving the lot of the country's Roma minority has not materialised. "Tolerance isn't taught at school, nor at home," said Krassimir Kanev from rights group the Bulgarian Helsinki Committee, saying people in the EU's poorest country "are easily manipulated." "Those behind the social unrest are young people frustrated by the lack of opportunities resorting to aggression and nationalism as somewhere to belong," analyst Antonina Jeliazkova told the Capital weekly. The outbreak of tensions amid campaigning for presidential and local elections on October 23. Several organisations including Organization for Security and Co-operation in Europe (OSCE) and Amnesty International have called for the Bulgarian government to take urgent action. The disturbances "underline the urgency of combating racially-motivated extremism and making progress with the integration of Europe?s Roma populations," the OSCE said. Patriarch Maxim, head the Bulgarian Orthodox Church, on Friday appealed to Bulgarians "to not let anger drag them into violence."