A top Turkish general has been jailed pending trial over an alleged plot to overthrow the government in 2003.

Commander General Bilgin Balanli was arrested as a suspect in the ongoing Sledgehammer case. He is the highest ranking active-duty military figure among 160 serving and retired officers charged with plotting a coup.

The case has exacerbated strains between Turkey’s secularist military and the ruling party with its Islamist roots ahead of the June 12 election.

In a separate development, a probe has been launched into the man who lead the 1980 military coup, former general and one time president, Kenan Evren. Although now 93, he is to be questioned under reforms to the constitution.

It now means those involved in Turkey’s bloodiest period in history can be prosecuted. After the coup, 650,000 Turks were arrested. Some 500 received the death penalty and hundreds more died in jail having been tortured, Euronews reported.