Twenty-eight military officers, including a four-star general, have gone on trial in Turkey in connection with an alleged plot to overthrow the country's Islamic-rooted government — the first time a serving general has been brought in front of a civilian court.

General Bilgin Balanli appeared Monday before the court, along with the 27 other officers, on charges of seeking to undermine the government. General Balanli was set to become commander of the air force until his detention three months ago.

Prosecutors claim he is part of an army conspiracy called “Sledgehammer.” They say the alleged plot included plans to cause panic across Turkey, including triggering a conflict with neighboring Greece and bombing mosques in Istanbul. The ensuing chaos would have allowed the military to launch a coup and unseat Prime Minister Recep Tayyip Erdogan, who came to power in 2002.

The defendants have maintained the so-called plot was just a war games contingency exercise and that the evidence against them has been fabricated. Observers question the reliability of the evidence, and the defendants' lawyers say police admitted earlier this year that they had planted incriminating evidence.

If convicted, the officers face up to 20 years in jail. More than 200 officers have been detained as part of the probe.

Long-running tensions between Turkey's secularist military and Mr. Erdogan's Islamic-rooted government came to a head last month with the sudden resignations of the country's top four military commanders.

The Turkish army has forced four governments from power since 1960.