ISTANBUL, April 10, 2026 (BSS/AFP) - The corruption trial of Istanbul's jailed opposition mayor entered its second month Thursday, in a case widely seen as a major setback for Turkey's opposition. Jailed since March last year, Ekrem Imamoglu of the main opposition CHP party is accused of running a vast criminal network he allegedly influenced "like an octopus". Prosecutors want him jailed for 2,430 years. "In this case, there is only one criminal organisation, and that is the prosecution!" said Imamoglu, President Recep Tayyip Erdogan's main rival, this week, again denying the accusations. "This is a political trial, in which the role of the law is very limited. But the lawyers are trying to steer the proceedings toward legal grounds," Istanbul Bar Association president Ibrahim Kaboglu told AFP. "However, that doesn't mean that in the end, we'll have a verdict that respects the law", he added. The mass trial at the Silivri courthouse on Istanbul's outskirts involves more than 400 defendants -- 107 of whom remain in detention. The judge last week ordered the release of 18 of them pending trial. Kaboglu condemned the continued detention of a large number of defendants as "unconstitutional". "The defendants should, in principle, appear in court as free men," he told AFP. -'Open-air prison'- "The efforts to keep our friends in prison ... are aimed at halting the CHP's march toward power," CHP leader Ozgur Ozel said Wednesday at the opening of a football pitch in Istanbul's Sisli district, whose mayor is also in jail. As the marathon trial drags on, legal pressure has tightened around the opposition. Four CHP mayors, including the mayor of Bursa in northwest Turkey -- the fourth-largest city -- have been arrested since the Imamoglu trial began on March 9. Erdogan's ruling AKP party on Thursday won control of Bursa after its mayor was jailed last week on charges including leading a criminal organisation and corruption, dealing another blow to the opposition. "They (the government) have turned Turkey into an open-air prison ... for all those who pose a threat to the regime," said the CHP leader, who is widely seen as the potential opposition candidate in the 2028 presidential vote. Imamoglu was thrown in prison on the day he was named the CHP's presidential candidate. He is seen by many as the only figure capable of defeating Erdogan at the ballot box. - 'God's justice' - Human Rights Watch has condemned "arbitrary restrictions" affecting journalists and lawyers covering the trial, saying they violate Turkish and international legal requirements for public hearings. Sevgi Sancar, a 60-year-old housewife who attended the CHP event at the football pitch this week said she believed Imamoglu and other jailed CHP officials "have no chance of being released before the presidential election". "I don't trust the justice system. There is no justice!" she said. "We don't trust the Turkish justice system, only God's justice," said Mine, a 50-year-old engineer who declined to give her last name. "But we haven't lost hope. Sooner or later, they'll all be released, because they're all innocent," she added.