Turkey's state-run Anatolia news agency reported that the trial of 56 Turks accused of being part of an alleged plot to topple Turkish Prime Minister Recep Tayyip Erdogan's Islamic-oriented government began on Monday. Prosecutors claim retired Gens. Hursit Tolon and Sener Eruygur are accused of being among the ringleaders of the secularist Ergenekon gang, which supposedly conspired to trigger a military takeover by creating chaos through a string of political assassinations and other violence. Other suspects on trial include Turkish politicians, businessmen and journalists. Tolon and Eruygur, who insist they are innocent, were the highest-ranking ex-soldiers to be charged in the case. They face life in prison if convicted on charges of establishing and leading a terrorist organization to overthrow the government. Eighty-six other suspects are being tried separately, accused of being part of Ergenekon, in a separate case that began in October. The 56 on trial Monday were detained and charged over the past few months as part of an investigation that grew out of the first Ergenekon case. Also on Monday, the Istanbul Chief Prosecutor's office said it had drafted a detailed indictment against 52 other suspects - a third group of people charged in the Ergenekon case. It said the new indictment was 1,454-pages long but would not provide further information, saying it still needed to be approved by a court. No trial date has been set for the third group of suspects. The investigation into Ergenekon was launched in 2007 when police found a cache of weapons in the home of a retired military officer. The Ergenekon gang is suspected in attacks on a newspaper and a courthouse, and plots to kill the prime minister and author Orhan Pamuk, Turkey's Nobel laureate.