Anti-government protesters carry their belongings as they walk towards the Royal Plaza to take their transport to return home, a day after a coup was declared in Bangkok May 23, 2014. [Photo/Agencies]

The anti-Thaksin protesters had demanded electoral changes that would end the Shinawatras' success at the ballot box. Thaksin or his parties have won every election since 2001.

Thai army chief announces military coup

Thaksin's "red shirt" supporters were dismayed and angry but said they had no immediate plans for protests. Those who had been protesting in Bangkok dispersed peacefully after the coup.

But many political analysts were predicting tension and violence. Protests would be a major test for Prayuth, who commands an army known to contain some Thaksin sympathisers.

In 2010, more than 90 people were killed in clashes, most when the army broke up protests against a pro-establishment government that had taken office after a pro-Thaksin administration was removed by the courts in 2008.

Investors have generally taken Thailand's upheavals in their stride and the market reaction to the coup was muted.

The baht was, at around 32.60 per dollar, firmer than its low point on Thursday of 32.70. The stock market opened down 2 percent but rallied to end 0.6 percent lower.

Thailand's economy contracted 2.1 percent in the first quarter of 2014 largely because of the prolonged unrest, which has frightened off tourists and dented confidence, bringing fears of recession.