Turkey ? Two retired generals were jailed Sunday in connection with an alleged plot to topple Turkey’s Islamic-rooted government, the highest-ranking ex-soldiers detained as part of the probe, a news report said.

The two, arrested late Saturday, were among 21 people rounded up in the past week in the investigation into an alleged pro-secular and nationalist network called “Ergenekon,” the state-run Anatolia news agency said.

Retired Gen. Hursit Tolon, who once headed the paramilitary force, and former top army commander Sener Eruygur, who helped organize a series of anti-government rallies last year, were being held at an Istanbul jail.

No charges have been filed, and details about the alleged plot were sketchy Sunday.