Violent clashes between pro- and anti-government protesters on the streets of Bangkok.
Troops joined police on the streets for the first time.
At least one man was killed and some 34 injured in the fighting here - and after a hundred days of anti-government protests, the government has now imposed a state of emergency.
Prime Minister Samak Sundaravej promised the emergency would only last a few days:
(SOUNDBITE) (Thai) PRIME MINISTER SAMAK SAYING,
"This situation gives me no alternative. This is the mildest solution within the limited choices, to declare a state of emergency only in the city of Bangkok, in order to solve this problem, in accordance with the law."
Samak's opponents, the People's Alliance for Democracy, argue that Samak is an illegitimate proxy for the disgraced former leader Thaksin Shinawatra, now in exile in London.
Thaksin was ousted by the military in a coup two years ago.
The presence of soldiers on the streets is a reminder how fragile democracy can become.
Benet Allen, Reuters