ISTANBUL - The head of the Turkish branch of Amnesty International rejected accusations of terrorism on Wednesday, saying she had nothing to regret, at a trial of 11 activists that has become a flashpoint in Ankara's tensions with Europe.A group of around 50 people from human rights groups, foreign consulates and women's rights groups stood outside the Istanbul court holding signs reading "Free Rights Defenders."Idil Eser spoke on the first day of the Istanbul trial that involves a German and a Swedish national as well as Turkish activists. They face up to 15 years jail if convicted."I don't understand how I can be associated with three different terrorist organizations by having attended a workshop," she said. "I don't have anything to regret. I just did my work as a human rights defender."The 11 were detained in July after participating in a workshop on digital security held on an island near Istanbul. Pro-government media have said the workshop was part of a broader plot to sow discord in Turkish society.Another accused, Ozlem Dalkiran, a member of the Turkish arm of the Citizens' Assembly, a European rights group, told the court: "I have no idea why we're here."The activists face a range of charges, including helping armed terrorist groups such as the Kurdistan Workers Party (PKK) and the network of the US-based cleric Fethullah Gulen, accused by Ankara of engineering last year's coup attempt.The prosecutor has cited Amnesty's links to jailed hunger strikers and alleged that some of the defendants had contact with people who had downloaded the encrypted messaging app used by the coup plotters.Authorities have jailed more than 50,000 people pending trial in a crackdown following the failed military coup. President Tayyip Erdogan says the purges across society are necessary to maintain stability in a key NATO country bordering Iran, Iraq and Syria.European allies fear he is using the investigations to check opposition and undermine the judiciary.