Istanbul, Turkey (CNN) -- Six Turkish journalists were among at least 11 people seized in police raids Thursday in a longstanding probe over an alleged plot to overthrow the government, Turkish media reported.
Police in Istanbul and Ankara conducted early morning operations in connection with the so-called Ergenekon plot -- under investigation since 2007, the Anatolian Agency and CNN Turk said, and the raids follow a sweep of searches and detentions against journalists last month.
One of the detained is Ahmet Sik, who co-authored two books on Ergenekon and was facing trial on charges of "violating secrecy of an investigation" in those books. His attorney spoke on television about the detention of his client, who was seen put in a car and driven away by authorities.
Another is Nedim Sener, a newspaper columnist and writer, who wrote two books and many articles about the assassination of Armenian-Turkish newspaper editor Hrant Dink in 2007.
He has been fighting in court over his work, in which he has accused Turkish authorities of failing to stop Dink's murder and said sources told him recently he's at the top of a list of reporters to be imprisoned.
Asked about the searches and detentions of journalists, Interior Minister Besir Atalay told reporters in Ankara that this was "entirely the decision of the judiciary."
While Turkey's democratic system has been seen as a political model for the Muslim countries undergoing change, there have been fears that the Islamic-rooted government of Prime Minister Recep Tayyip Erdogan has been targeting reporters and dissenters.
Over the last two years, Turkey has dropped from 102 to 138 on the press freedom index of Reporters Without Borders, and it now sits among the bottom 40 countries of the world when it comes to freedom of the press.
In its review of press freedom in Turkey last year, the Committee to Protect Journalists said "authorities paraded journalists into court on anti-terror, criminal defamation, and state security charges as they tried to suppress critical news and commentary on issues involving national identity, the Kurdish minority, and an alleged anti-government conspiracy."
On February 18, Turkish authorities arrested three journalists from a dissident news website, Oda TV, following a raid on their homes and offices.
In an interview with CNN in November, Sener said journalists in Turkey are feeling "direct pressure from the government. They can easily corner the reporter they don't like for news they don't like."
While the police continued searching Sener's house and car, his neighbors hung Turkish flags on their windows in solidarity with the journalist, one neighbor told CNN.
In a column Tuesday in the Posta newspaper, Sener wrote that sources "very close to police" say his "name is written on top of the list of journalists to be sent to prison."
"Those who see me treat me like a patient with a terminal disease who is about to die, yet doesn't know yet. Those who avoid eye contact and greet me with a forced smile have increased. However, I don't know what 'crime' I committed. If doing your job is a crime, yes I am guilty," he wrote.
CNN's Ivan Watson and Talia Kayali contributed to this report