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Thailand's ruling military on Friday summoned the entire ousted government and members of the politically influential family at the heart of the country's long-running conflict, a day after it seized control of this volatile Southeast Asian nation in a non-violent coup.

There was virtually no military presence on Bangkok's streets, which were less crowded than usual but still filled with vendors and people heading to work after a 10 p.m. - 5 a.m. curfew the night before. There were no reports of overnight violence.

Countries including the United States, Japan and Australia expressed concern and disappointment over the coup, with the U.S. saying there was "no justification" for the takeover, Thailand's second in eight years.

It was unclear why more than 100 people -- including the ousted prime minister and several members of the influential Shinawatra family -- were ordered to report to the army, which said it was summoning the high-profile figures "to keep peace and order and solve the country's problems."

Former Prime Minister Yingluck Shinawatra, sacked earlier this month for nepotism by the Constitutional Court, and her temporary replacement Niwattumrong Boonsongpaisan, arrived at an army compound in Bangkok, Yingluck's aide confirmed. After about 30 minutes, Yingluck left the facility and was taken to another army location by soldiers, the aide said. It was unclear how long she would remain there.

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The coup was launched Thursday while the military hosted a meeting of political rivals for what was billed as a second round of talks on how to resolve the country's political deadlock. After two hours of inconclusive talks, armed soldiers detained the participants, including four Cabinet ministers, and army chief Gen. Prayuth Chan-ocha appeared on national television to announce the takeover.

Prayuth justified the coup as a necessary move to restore stability and "quickly bring the situation back to normal" amid increasing spasms of violence that together with controversial court rulings had rendered the government powerless and the country profoundly divided between the wealthy urban elite who disdain the Shinawatra family and their supporters among the rural poor majority.

The military suspended the constitution and the Cabinet and banned gatherings of more than five people -- a risky bid to end half a year of political upheaval that many fear will only deepen the nation's crisis.

"We're likely to see dark days ahead," said Thitinan Pongsudhirak, a political analyst at Bangkok's Chulalongkorn University, referring to the possibility of violent resistance from the ousted government's supporters.

So far, there was little sign of military control on the streets of Bangkok. Traffic was lighter than usual and schools across the country were ordered closed, but life in the bustling metropolis of 10 million people appeared relatively normal. Like any other morning, street vendors set up their food stalls, commuters headed to work and delivery trucks made their rounds.

"At first I was surprised and I thought it would affect my life in many ways but after re-thinking it several times I realize military protection makes me safe," said Bangkok resident Passawara Pinyo.

"I expected it to happen anyway," said office worker Montri Chanthasuthi, "it was just a matter of when."

The main indication of military presence was on television, where regular programming was replaced by a static screen showing military crests and the junta's self-declared name: National Peace and Order Maintaining Council. Patriotic music filled air time, interrupted by occasional announcements from military officials.

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.

The army, which imposed martial law in a surprise move Tuesday that many sensed was a prelude to taking full power, imposed a nationwide curfew Thursday that began at 10 p.m. -- a clear sign it was concerned about potential unrest.

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.

Australian Foreign Minister Julie Bishop said her country was "gravely concerned" about the situation in Thailand. She called the coup a "regrettable development" that is prompting her government to review its relationship with the Southeast Asian nation, a major destination for Australian tourists.

Japan called the coup "deeply regrettable" and urged that democracy be quickly restored.