ANKARA: The former commander of Turkey's land forces has been jailed pending trial in a widening investigation of the toppling of Turkey's first Islamist-led government in 1997, state media said on Thursday.

General Erdal Ceylanoglu, who is believed to have ordered tanks onto the streets outside the capital ahead of the military intervention 16 years ago, joined dozens already remanded in custody ahead of the court case.

The inquiry into the ousting of former prime minister Necmettin Erbakan is part of a wider extensive judicial investigation into the once-supreme Turkish military, whose power has been sharply curbed over the past decade.

In power since 2002, Prime Minister Tayyip Erdogan's Justice and Development Party, AKP, which itself has Islamist roots, has made curbing the military's political influence one of its main missions, and state prosecutors have pursued officers suspected of conspiring against current and former governments.

Political reforms in 2010 to remove the immunity of old coup leaders have given prosecutors room to delve deeper into Turkey's history. The sight of police seizing grey-haired former generals, unthinkable a decade ago, has become a familiar one in Turkey in recent years.

Erbakan, who died of heart failure aged 85 in 2011, pioneered Islamist politics in Turkey, a largely Muslim country with a secular state order, and paved the way for the subsequent success of Erdogan's AKP.

The investigation into the events of 1997, dubbed the "post-modern coup" for its bloodless nature in contrast to three outright coups in 1960, 1971 and 1980, has especial significance for Erdogan who was a member of Erbakan's party.

Also detained overnight was retired major general Yucel Ozsir. Their detention comes only two weeks after the jailing of four other retired generals in connection with the coup.

Turkey's state media Anatolian said the two generals were remanded in custody late on Wednesday after being summoned to an Ankara court along with two other retired generals and a serving colonel who were later conditionally released from custody.

The two generals were taken to a maximum security prison in Sincan, a town outside Ankara where Ceylanoglu is charged with commanding tanks onto the streets during the upheaval in 1997.

While Erdogan has promoted the trials as part of the process of ending the generals' political power, he has more recently called for the investigations to be wrapped up more quickly and has hit out at the lengthy pre-trial detentions of hundreds of officers on conspiracy charges.

More than 300 military officers were sentenced to jail in September for plotting to overthrow Erdogan in 2003. Nearly 300 other people - including politicians, academics, journalists and retired army officers - are on trial on charges of orchestrating political violence.