6 January 2012 Last updated at 06:47 ET

Turkey coup plots: Major suspects

Hundreds of military officers have been arrested in Turkey over the last four years in connection with allegations of a number of coup plots. Many of the accused are alleged to be members of a clandestine organisation called Ergenekon, and some are said to be involved in the Sledgehammer case, based on a military seminar alleged to be a rehearsal for a coup.

Several trials are running concurrently and no-one has yet been convicted. The following are some of the most senior officers and other key figures charged over the affair.

General Ilker Basbug

Commander of the Turkish armed forces from 2008 to 2010, Gen Basbug is the most senior officer implicated in the alleged coup plots. He was arrested on 5 January and is expected to face initial charges of "gang leadership" and attempting to topple the government.

His arrest follows allegations made by officers involved in another trial that he ordered the creation of anti-government websites. He has rejected the charges, describing as "tragicomic" attempts to implicate him in terrorist activity.

General Hasan Igsiz

Former head of the prestigious First Army and deputy chief of the general staff operations department, Gen Igsiz was proposed as head of the land forces in 2011. But his candidacy was blocked because he had been named in one of the plots.

He has been described as "the number one suspect" and stands accused of orchestrating an internet campaign to discredit the governing AK party. He was arrested in August 2011.

General Cetin Dogan

Another former First Army commander, in 2003 Gen Dogan hosted at his headquarters a war simulation workshop, alleged to be a dress rehearsal for a coup and forming the basis of the so-called "Sledgehammer" case. He maintains that the workshop was aimed at preventing a hypothetical situation involving political unrest.

He is also accused of preparing documents related to Sledgehammer, but it is not clear whether any of them carry his signature. He was arrested in July 2010.

Admiral Ozden Ornek

Former navy chief (2003-05) Adm Ornek is alleged to have written a diary containing action plans for three coups that were being prepared.

The diary was published by a magazine in 2007, which was subsequently closed down by military prosecutors. He maintains that the diary was a forgery.

He was arrested in July 2010 in connection with the Sledgehammer case.

General Veli Kucuk

Retired general accused in the first Ergenekon indictment in October 2008 of running a secret unit within the police responsible for bombing and killings. Also accused of involvement in an attempt to assassinate the writer Orhan Pamuk. Arrested in July 2008.

General Sener Eruygur

Former head of the Gendarmerie General Command (JGK) and currently the chairman of the Ataturk Thought Association, an organisation which aims to uphold the principles of founder of the secular Turkish state. He is alleged to have taken part in two coup attempts in 2004, and comes under the second, March 2009, indictment.

General Halil Ibrahim Firtina

Air Force commander from 2003 to 2005. Arrested in connection with the Sledgehammer case in July 2010.

General Aytac Yalman

Land forces commander 2002-04. Arrested in connection with the Sledgehammer case in July 2010.

General Nusret Tasdeler

Former commander of Aegean Army and head of the army's educational command. Arrested in August 2011 for setting up anti-AK websites.

General Ismail Pekin

Former general staff intelligence chief, arrested in August 2011.

Nedim Sener

A highly acclaimed journalist for the opposition newspaper Milliyet, Nedim Sener won a press freedom award for a book he wrote about the assassination of the ethnic Armenian writer Hrant Dink, in which he blamed the security forces.

He was arrested on March 2011 for alleged involvement in the Ergenekon plot, said to be acting as its media wing, and has been on trial since November. He and 12 fellow journalists argue that they are being targeted for the content of their articles and that incriminating files found on their hard drives were placed by hackers.

Ahmet Sik

A journalist who wrote a book about the Ergenekon group, and who is known for reporting on human rights abuses and on what he describes as illegal Islamist networks operating within the Turkish state. Arrested in March 2011 with Nedim Sener.