Turkish police detained 26 people, including a journalist and a union leader on Thursday, media said, in a probe into an alleged coup plot that has rattled markets and fuelled tension between the government and the army.
A police chief and an officer were also brought to Istanbul from the Mediterranean city of Antalya for questioning in the widening investigation, state run Anatolian news agency said.
Eighty six people, including retired senior officers, are on trial over suspected links to a nationalist group known as "Ergenekon" that is accused of plotting the overthrow the Islamist rooted AK Party government in EU candidate Turkey.
More detentions were taking place in 13 provinces on Thursday, and police were searching the offices of a metal union, broadcasters said.
Turkey's powerful military, which has unseated governments four times in the past 50 years, has criticised the investigation and denied any links to an alleged plot to conduct bombings and assassinations to clear the way for a coup.
A wave of detentions earlier this month, including active officers, further strained relations between the government and the secular establishment made up of the military and judiciary.
Critics says the governing AK Party is carrying out the arrests as revenge for a 2008 court case that sought to ban the party for anti secular activities.
The ruling AK Party, which has roots in political Islam but also embraces centre right and nationalist elements, denies this.