Thai "Red Shirt" protesters set roadblocks in a street of Bangkok, capital of Thailand, on May 15, 2010. The intense political situation has continued in Bangkok on Saturday. [Xinhua/Thana Nuntavoranut]

It is recorded by the CRES that on Friday night 16 M79 grenades were fired at security personnel having stationed at various locations, acting government spokesman Panithan Wattanayakorn said.

The military operations have decreased the protesters' number at the Rathchaprasong area to about 6,000, Panithan said.

Meanwhile, the Pathumwan District Court in central Bangkok sentenced 27 protesters to six months in jail, Department of Special Investigation (DSI) Director-General Tharit Pengdit said.

These protesters, who were arrested on Friday, were found guilty of violating the emergency law imposed in the capital by engaging in political gatherings of more than five people.