Thailand's junta said Tuesday former Prime Minister Yingluck Shinawatra had been released from military detention and allowed to return home, in the first official confirmation of her whereabouts since she was detained last week.

Yingluck, who led the former Puea Thai government until she was removed by a controversial court ruling in early May, was detained on May 23 after reporting to the army.

"She (Yingluck) has been released," junta spokesman Colonel Winthai Suvaree said, without specifying when she was freed.

"Everyone released must sign an agreement to inform the National Council of Peace and Order about their whereabouts clearly," he said, adding that related to major movements only and she would be allowed to go "shopping".

He did not confirm if her home was being watched over by soldiers.

Yingluck was among scores of leading figures from both sides of the political divide to be detained by an army sweep after it seized power on May 22.

For days her exact location remained a mystery.

She is the younger sister of billionaire Thaksin Shinawatra, who lives in self-imposed exile to avoid a corruption charge but who sits at the heart of the nation's deep political divide.

Thailand's coup leader Army Chief Prayut Chan-O-Cha has imposed sweeping curbs on the media, ordered the detention of influential political figures and warned he will not tolerate further protests by anti-coup demonstrators.