At least three people have been killed and dozens injured in a series of grenade explosions in the business district of Bangkok.
The blasts came as hundreds of pro-government demonstrators were staging a rally in the Thai capital to call for an end to weeks of mass protests by the anti-government "Red Shirts".
The city was hit by five blasts, which sent panicked people running through the streets and fleeing an elevated train station.
Army spokesman Colonel Sansern Kaewkamnerd said five M-79 grenades were fired from grenade launchers.
Three fell through the roof of the Saladaeng Skytrain station in the centre of Bangkok's business district.
A fourth exploded on the pavement near the five-star Dusit Thani Hotel and the fifth near a bank, he said.
Thailand's deputy prime minister confirmed at least three people had been killed and 75 wounded, including four foreigners.
He also said the government had no plans to crack down on the protesters because there were women and children among them.
The Reds, who accuse the government of being undemocratic and elitist, have fortified their rally base in central Bangkok with barricades made from bamboo poles and piles of car tyres.
Hundreds of fully armed troops have poured into the area since Monday to keep the protesters from marching into the business district.
British tourist Liz Beswick, from Bournemouth, said the situation in Bangkok was "horrible".
She said: "There were people in red everywhere which was really intimidating.
"If you're not wearing red you stand out like a sore thumb and everyone stares at you.
"I was pretty scared to be honest."
:: The Foreign Office has changed its travel advice for Bangkok because of the risk of violence breaking out without warning.
Britons should avoid all but "essential" travel to the Thai capital, the Government said.