REPUBLIKA.CO.ID, BANGKOK - Thai authorities were "very seriously" considering a state of emergency after a weekend of violence in the capital where protesters had been trying for more than two months to bring down the government, the security chief said on Monday.

The emergency decree gives security agencies broad powers to impose curfews, detain suspects without charge, censor media, ban political gatherings of more than five people and declare parts of the country off limits.

The violence is the latest episode in an eight-year conflict that pits Bangkok's middle class and royalist establishment against poorer, mainly rural supporters of Prime Minister Yingluck Shinawatra and her brother, ex-premier Thaksin Shinawatra, who was toppled by the military in 2006.

"We're prepared to use the emergency decree ... Everyone involved including the police, the military and the government is considering this option very seriously, but has not yet come to an agreement," National Security Council chief Paradorn Pattantabutr told Reuters after meeting Yingluck.

"The protesters have said they will close various government offices. So far, their closures have been symbolic, they go to government offices and then they leave." he said. "But if their tactics change and they close banks or government offices permanently, then the chance for unrest increases and we will have to invoke this law."

The emergency decree gives security agencies broad powers to impose curfews, detain suspects without charge, censor media, ban political gatherings of more than five people and declare parts of the country off limits.

The size of the demonstrations in Bangkok has declined, but the Centre for the Administration of Peace and Order (CAPO), a body grouping government and security officials, said small protests had spread to 18 other areas.

The protests led by opposition firebrand Suthep Thaugsuban were triggered by Yingluck's move last year to attempt to push through a political amnesty that would have allowed her brother Thaksin to return home.

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