Turkey's prime minister vows to continue Gezi Park development People wave Turkish flags and shout slogans against Recep Tayyip Erdogan during a protest on Taksim Square in Istanbul. Photograph: Aris Messinis/AFP/Getty Images Turkey's prime minister, Recep Tayyip Erdoğan, has vowed to press ahead with the controversial redevelopment of a square in Istanbul, in a move that puts him on a collision course with tens of thousands of anti-government protesters and could provoke further unrest across the country. Speaking in Tunis before flying back to Istanbul on Thursday evening, Erdoğan acknowledged that some of those who had defended Istanbul's Gezi Park had acted for genuine environmental reasons. But he also said "terror groups" were behind Turkey's biggest demonstrations in years and hinted at a plot involving radical Marxist-Leninists. Public property was damaged during the Gezi Park protests. The Taksim [Square] project is a project that will make Istanbul more beautiful," Erdoğan said. He pledged to press ahead with the building of an Ottoman barracks on the site next to the park, despite the vehement objections of protesters. "You cannot rule a state with the logic of give and take," he said. The prime minister's remarks were less abrasive than his comments earlier this week when he branded his critics as looters and fringe extremists. Most of those opposing him are secular, middle-class Turks, incensed by new restrictions on alcohol consumption and his unilateral style of decision-making. Turkey's stock market sank as he spoke, losing 4.7% of its value amid expectations of further violence. Protesters massing in Gezi Park - now the scene of a vast Glastonbury-style democracy festival - branded him out of touch with the public mood. He's very stubborn. I can't really understand him," Ayce Malkoc, 26, said. We will still go on protesting. We need green space. Another protester, Lale, who declined to give her second name, said: "We don't want to fight. But we are not going to give up either. Erdoğan did not say sorry but he did refer to an apology made by his deputy, Bülent Arınç, who on Tuesday admitted the police had behaved excessively, using too much teargas. Striking a defiant tone, Erdoğan said his Islamist-rooted Justice and Development party (AKP) had won three elections and notched up 21 million votes. We are against the majority tyrannising the minority. But we are definitely against the minority tyrannising the majority. Political analysts said Turkey's leader continued to misinterpret the reasons behind the protests, which spread last week from Istanbul to the capital, Ankara, and other cities. "He believes there is a plot to overthrow him with the complicity of external and international forces," said Cengis Aktar, a professor of political science at Istanbul's Bahcesehir University. Erdoğan has returned from abroad as angry dad. This is bad. It means he is preparing for confrontation. Earlier this week Erdoğan denounced Twitter. On Thursday Turkey's EU minister, Egemen Bagis, heaped blame on the international media. Speaking at a press conference in Istanbul, he told the BBC's Middle East correspondent Jeremy Bowen that the corporation had encouraged the protesters to commit acts of vandalism. Turkey's pro-Erdoğan channels, by contrast, failed to report on the protests for days, instead screening a documentary on penguins. So far three people have been killed and more than 4,000 injured in a dozen cities. Some 915 have received hospital treatment, with eight in intensive care and four critical. A policeman who fell from a bridge while chasing protesters in the southern city of Adana became the third fatality after dying of his injuries. Turkey's interior ministry on Thursday insisted the authorities had behaved with restraint: "The police have done their duty selflessly and legally in hundreds of unreported demonstrations." Despite Erdoğan's latest pronouncements, the future of Taksim Square is unclear. The prime minister announced that he was dumping the unpopular idea of a shopping mall but would instead build a "stronger and better cultural centre" - a reference to the Ataturk cultural centre facing the square which has been derelict for several years. Protesters have draped giant anti-Erdogan banners across its modernist facade. "They [the protesters] want to block the good things the AKP has been doing," he said. Erdoğan also linked the protests with an attack in February on the US embassy in Ankara, in which a suicide bomber killed himself and a Turkish security guard. The bomber was identified as a member of the Revolutionary People's Liberation Party-Front, an outlawed Marxist-Leninist party. Although several socialist and anarchist groups have erected tents in Gezi Park, there appears to be scant connection; most of the protesters have no party affiliation and little interest in formal politics. The square is currently a giant pedestrian zone. Barricades erected by protesters remain in place after riot police pulled out of the area entirely on Saturday. As well as watermelons and kebabs, street vendors are now selling Guy Fawkes-style masks, as used by the group Anonymous, and swimming goggles to protect against gas attacks.