Article published on the 2008-09-02 Latest update 2008-09-02 09:12 TU
Thousands have been protesting over the past week, calling for the prime minister to resign.
The People's Alliance for Democracy opposition movement accuses Samak's government of corruption and of being a proxy for deposed Prime Minister Thaksin Shinawatra.
Samak has refrained from using force to clear the anti-government protestors from Government House, which they have occupied for a week.
But after the early morning violence, Samak said that they had to be moved.
"I had no other choice but to declare a state of emergency in Bangkok in order to solve the problem once and for all," said Samak in a nationally televised press conference.
The army was called in early Tuesday to help the police. Army commander Gerneral Anupong Paojinda said that the military was "on the people's side" and added that troops would only be armed with batons and shields and would not use force.
No solution emerged from Sunday's 11-hour emergency meeting in parliament.
The protesters say that they will stay put.
The 200,000-strong State Enterprises Workers' Relations Confederation called for a strike Wednesday, saying they would cut power and water supplies to government agencies.
"We will stop utilities services to government agencies to put pressure on the government to quit and stop damaging our country," said Sawit Kaoewan, secretary of the confederation.
Meanwhile, Thailand's Election Commission on Tuesday called for disbanding the ruling People Power Party over claims of electoral fraud committed in last December's election.
The commission forwarded its findings to the office of the Attorney General, which will decide whether to submit the case to the Constitutional Court for a final ruling.