Thailand coup leaders hold ex-PM Yingluck Shinawatra

Ousted members of Thailand's former government turned themselves in to the country's new military junta Friday, as soldiers forcefully dispersed hundreds of anti-coup activists who defied a ban on large-scale gatherings to protest the army's seizure of power.

At least two activists were detained by troops during the protest in downtown Bangkok, which descended into scuffles but ended without injury and marked one of the first open challenges to the military since Thursday's coup.

The junta, though, remained firmly in charge, summoning more than 100 top political figures the entire ousted government, their associates and a handful of their opponents. It also banned those on its wanted list from leaving the country.

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Among the officials who showed up at an army compound in Bangkok by midday were former Prime MinisterYingluckShinawatra, sacked earlier this month for nepotism by the constitutional court, and her temporary replacementNiwattumrongBoonsongpaisan, according toYingluck'saideWimRungwattanachinda.

After about 30 minutes,Yingluckleft the facility and was taken to another army location by soldiers, saidWim, who later added that it appeared she would not be immediately released.

It was unclear what the military's intentions beyond the summons, which it said had been issued "to keep peace and order and solve the country's problems."

By nightfall, dozens of the VIPs who turned themselves in were still being held, although at least eight ex-cabinet ministers had been released.

One, Education MinisterChaturonChaisang, an outspoken critic of the military's intervention in politics, remained in hiding.Chaturonsaid in a Facebook post that the coup would only worsen the country's political atmosphere. He vowed not to turn himself in, but said he would not resist arrest.

Most of the country was calm, and there was little military presence on Bangkok's streets. Although life had largely returned to normal during the day, an overnight curfew from 10 p.m. to 5 a.m. was still in effect.

There were no reports of any unrest, including the former government's political strongholds in the north. In the northeast city ofChiangMai, about 100 anti-coup demonstrators also took to the streets, but no violence was reported and the protesters dispersed on their own.

The army staged the coup Thursday just after a military-hosted meeting of political rivals to resolve the country's political deadlock.

After two hours and no resolution, armed soldiers detained the participants, including four cabinet ministers, and army chief Gen.PrayuthChan-ochaappeared on national television to announce the takeover. Hours later, the junta suspended the constitution and banned gatherings of more than five people.

Prayuth says coup necessary

Prayuthjustified the coup as a necessary move to restore stability amid increasing spasms of violence that together with controversial court rulings had rendered the government powerless.

But there are fears the power grab will only lead to more violence and simply deepen the nation's crisis.

Thursday's dramatic events were the latest response to a societal schism laid bare after the 2006 coup deposed former Prime Minister Thaksin Shinawatra, the older brother of Yingluck and a billionaire tycoon whose populist movement has won every national election since 2001. Thaksin lives in self-imposed exile to avoid corruption charges, but he still wields enormous influence over Thailand's political affairs and remains at the heart of the ongoing crisis.

It is a divide that has led to upheaval multiple times in recent years. The latest crisis alone has left 28 people dead and more than 800 wounded since November.

U.S. Secretary of State John Kerry condemned the takeover and warned it would "have negative implications for the U.S.-Thai relationship," but did not announce immediate punitive steps. The State Department said it was reviewing millions of dollars in aid.

"There is no justification for this military coup," Kerry said in a statement that also called for the release of detained political leaders and a return of press freedom.

British Foreign Secretary William Hague said his country looked to Thai authorities "to set out a quick clear timetable for elections to help re-establish the democratic framework of governance.

"There should never be recourse to violence: only by openly discussing the full range of issues can Thailand move forward and reach a more stable position," he said in a statement issued by the Foreign Office.