Eight years of turmoil
An election on February 2 failed to break the deadlock in Thailand, a country popular with tourists and investors but blighted by eight years of polarization and turmoil.
Protesters blocked voting in a fifth of constituencies, a result that left parliament without a quorum to approve a new government and Yingluck's Puea Thai Party limping on as a caretaker administration with limited powers.
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The deadlock has raised concerns about the long-term impact on an already weakening economy, with the caretaker government unable to approve spending on new infrastructure projects that would have supported growth.
The protesters are demanding that Yingluck resigns and makes way for an appointed "people's council" to overhaul a political system they say has been taken hostage by Thaksin, a telecoms billionaire who shook up Thai politics in the early 2000s with populist policies that harnessed the support of the populous but previously neglected north and northeast.
Thailand's army chief appealed for calm on Thursday ahead of a long holiday weekend, while reiterating that the coup-prone military was resolved to stay neutral.
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Protest leaders had urged supporters to come out in force over the weekend, and were planning "Love Thailand and Break-up with the Thaksin Regime" events in Bangkok on Friday, Valentine's Day, which coincides with a Buddhist holiday.
Rumours had swept Bangkok late on Thursday that the police planned to retake parts of the capital ceded to the protesters. "Police said they will disperse protesters ... We must prepare ourselves to fight back," PDRC leader Suthep said in a speech at one of the main protest sites on Thursday night.