Defendants are escorted under heavy security to court in the capital, Ankara, on Tuesday.

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Muslim cleric Fethullah Gulen is among those charged in absentia

Indictment asks for life in prison without parole for nearly 50 defendants

Istanbul, Turkey CNN  — 

Nearly 500 people accused of plotting to overthrow the Turkish government last year are in court on Tuesday in the country’s largest mass trial over the failed coup.

In a courthouse built specifically to try cases linked with the coup attempt, 486 went on trial on a long list of charges, including trying to assassinate the President, leading an armed terrorist organization and homicide, state-run news agency Anadolu reports.

Around 250 people were killed in the July 2016 attempted coup, many of them Turkish civilians. Anadolu reports that Muslim cleric Fethullah Gulen was one of seven people who had been formally charged in absentia. Turkish President Recep Tayyip Erdogan accuses Gulen of masterminding the coup attempt.

Gulen, who lives in exile in Pennsylvania, has vehemently denied involvement in the plot.

Defendants Kemal Batmaz (center) and Akin Ozturk (second left in row behind) arrive for their trial on Tuesday. Batmaz is a civilian and Ozturk served as a four-star general.

The indictment – which is more than 4,500 pages long – asks for life in prison without parole for nearly 50 of the defendants. It accuses the defendants of bombing the Turkish Parliament, roads and bridges around the presidential palace and the special forces directorate by aircraft.

Among those indicted are generals who allegedly oversaw the coup attempt, pilots and civilian coordinators. One pilot is accused of flying an F-16 jet that struck Parliament.

The trial is centered around activities at the Akinci Air Base outside Ankara, where the Turkish government says the coup attempt was organized and coordinated.

The trial is expected to take more than a month and is one of the most significant in connection with the failed coup.

Turkish courts have held several mass trials over the alleged plot and the government is continuing with a widespread purge of public institutions following the unrest.

It has detained around 150,000 people over the failed coup, Anadolu reports, around a third of whom have been released. Another third have been released with judicial controls placed on them.

The attempted overthrow and the government’s ensuing crackdown on the media, the political opposition, academics and security forces have been a divisive force in the country.

But there has been little public sympathy for the plotters.

A group of demonstrators gathered outside the heavily secured courthouse Tuesday with banners reading: “We want the death penalty for traitors.”

CNN’s Sarah Sirgany and Carol Jordan contributed to this report.