[JURIST] Thailand’s Prime Minister Yingluck Shinawatra [BBC profile] on Monday invoked a special security law in districts of Bangkok and nearby areas after protesters stormed and occupied several key ministries. The law, known as the Internal Security Act, gives police additional powers to block routes, impose curfews, ban gatherings and carry out searches. The demonstration against Shinawatra is the biggest since the 2010 anti-government protests when 90 civilians were killed in a military crackdown [TIME backgrounder]. On Monday, tens of thousands of demonstrators, led by Suthrep Thaugsuban, occupied [Bangkok Post report] 13 government offices. However, as the rallies have remained peaceful, the prime minister said there would be no need to expand enforcement of the Internal Security Act beyond the districts around the centers of government.

Thailand’s political system has been unstable since the 2006 military coup [AHRC backgrounder, PDF] by the Royal Thai Army against then-prime minister Thaksin Shinawatra [BBC profile], and the Bangkok crackdown has only exacerbated the instability. Following democratic party defeats in 2011, Abhisit Vejjajiva [BBC profile; JURIST news archive] resigned [Bangkok Post report] as prime minister. A month before his departure, he rejected a proposal [JURIST report] by the opposition party seeking a referendum to grant amnesty to those involved in the 2006 military coup. In February 2011, seven leaders of Thailand’s “red-shirt” pro-democracy movement [BBC backgrounder], another group that opposes the country’s current leadership, were released on bail [JURIST report] after being arrested on terrorism charges stemming from their involvement in the Bangkok protests. Last December, Thailand’s Department of Special Investigation (DSI) announced that Abhisit will be charged with murder [JURIST report] for his role in the 2010 Thai military crackdown on anti-government protesters. Earlier that year, members of the movement also petitioned [JURIST report] the International Criminal Court [official website] to launch a preliminary investigation into whether the government committed crimes against humanity during those protests.