Updated

The editor of a leading Turkish opposition newspaper has been formally arrested for allegedly spreading "terrorist propaganda," the state-run Anadolu news agency said Tuesday.

Oguz Guven, the editor of Cumhuriyet newspaper's online edition, was formally arrested Monday evening after being detained Friday.

Guven was arrested on the grounds that he bears legal responsibility for the newspaper's tweets, specifically in reference to a tweet on the death of prosecutor Mustafa Alper in a traffic accident last week.

The deleted tweet described Alper as having been "mowed down" by a truck, seen by many as an unsavory choice of words.

Alper, chief prosecutor of Denizli province in southwestern Turkey, filed the first indictment against the network of U.S.-based cleric Fethullah Gulen following last summer's coup attempt.

The Turkish government blames Gulen for orchestrating the July 15 coup, which he denies.

Citing the court decision, Anadolu said the tweet's wording stood against news principles and was chosen to create a "perception of warning" for prosecutors working against the Gulen network.

Reporting Guven's testimony, Cumhuriyet said the breaking news tweet was posted in a hurry, leading to an error in language, and was deleted in 55 seconds before a new tweet was issued. Guven said the phrase "mowed down" is often used to describe traffic accidents and was not ill-intentioned.

"We did not aim to commit a crime," Guven said, adding that the article linked to the tweet and other tweets are proof he did not praise a terror organization.

Prime Minister Binali Yildirim said Tuesday the judiciary would "do what's necessary to people using inappropriate expressions" following Alper's death.

Twelve journalists and senior staff members of Cumhuriyet are imprisoned pending trial on charges of "aiding terrorist organizations," including Gulen's network and Kurdish militants.

According to Platform 24 for independent journalism, 165 journalists are behind bars in Turkey. More than 47,000 people have been arrested since the failed coup.