Tens of thousands of anti-government protesters have gathered outside Government House in Bangkok calling for Prime Minister Yingluck Shinawatra and her administration to resign.
Some protesters climbed the fences but the gathering appeared to be mostly peaceful.
Yingluck said on Saturday the police would act with restraint if people tried to occupy public buildings, including their main target, her Government House offices.
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Coal's share of the power mix had fallen to 7%, while wind climbed to new highs to provide 15% of the country's electricity.
State Department spokeswoman Heather Nauert said Pence "was ready to take this opportunity."
Opposition activists said government forces have brought in more reinforcements in recent days.