Witnesses to events in the Thai capital tell the BBC News website what they have seen.
The situation is very unclear at the moment and Thai people like myself cannot receive any information from the media apart from the occasional pre-recorded messages that more or less suggested that everything is under control... I think everyone is wondering now why the state of emergency was called in the first place. It is fair to say that as Thai citizens we should be the first people to hear about this, not the people who attend the UN Assembly.
I was on my way to the airport from Hua Lampong Station, thereby passing through Government House. At least five tanks have blocked the roads but everything seems to be calm, restaurants are closed down and armed soldiers are patrolling on motorcycles.
NARUSS MAHAKKAPOND, BANGKOK
I was holding a meeting in downtown Bangkok and the meeting was interrupted and everyone was out of the building immediately. There are also troops of fully armed soldiers and tanks around Bangkok, including Chinatown. Now I am at my girlfriend's place. My place is next to the king's palace.
GREG JORGENSEN, BANGKOK
On 16th floor of apartment, view cloudy because of rain, tank at end of street. At home at my apartment right now, with a view across the city. Looks kind of deserted... My phone started ringing off the hook a few minutes ago with warnings from friends. All looks well from the balcony of my apartment building, but only time will tell. The thing is, Thaksin HIMSELF is the problem... Many people think that when he's gone, things will calm down.
RUSSELL MILES, BANGKOK
I took a taxi to Government House, or as near to it as we could. Troops and guys dressed in Swat-style gear are strolling around. There is a tense but fairly controlled atmosphere. Tanks are lined up blocking the streets, I saw a group of blokes bundling a cameraman and another chap into a van. We are taking photos, but not out in the open.
BILL HANSON, BANGKOK
As I emerged from the subway at Rama 4 and Sathorn I heard sirens and then saw a convoy of military vehicles head on to Sathorn Road with sirens blaring and buses of troops with guns at their sides. Haven't see this for many years here.
JOE P. THAWILVEJJAKUL, BANGKOK
We are seeing a large manoeuvres of armed vehicles near Government House area. This is definitely for real!