BANGKOK A series of grenade blasts shook Bangkok's business district on Thursday, killing at least three people and wounding 75, heightening tensions during a showdown between troops and anti-government protesters.
Five explosions hit an area packed with heavily armed soldiers and studded with banks, office towers and hotels. Four were seriously wounded, including two foreigners, according to hospital officials.
The M-79 grenades, fired with a shoulder-mounted launcher into an area where hundreds of pro-government protesters were gathering, were the same type that hit troops during a bloody clash with protesters that killed 25 people on April 10.
Troops, many armed with M-16 assault rifles, have poured into the area since Monday to contain the anti-government "red shirts," who have formed a barricade at an intersection leading into the bustling district also known for racy go-go bars.
The government said the grenades were fired from the red shirt protest area. Leaders of the red shirts, who have been demonstrating in Bangkok for nearly seven weeks seeking new elections, denied they were responsible.
Television footage showed blood splattered across sidewalks, office windows smashed and a chaotic scene as panicked residents carried the injured into nearly a dozen ambulances.
"It's worrying, seeing ambulances, people running away. The police and army don't seem to be in control," said Herman Koopman, a tourist from the Netherlands.
Ater the explosions, hundreds of pro-government protesters regrouped and hurled glass bottles and rocks at the red shirts until riot police forced them back with batons. The red shirts responded by throwing rocks and bottles back.
Local media said five people had been detained.
One explosion hit outside the headquarters of Charoen Pokphand Group, Thailand's biggest agribusiness group. Another landed near the Dusit Thani Hotel. Others struck parts of the district's main Silom Road.
After the blasts, troops blocked off roads with razor wire and trained their guns in the air looking to rooftops and an overhead railway system.
STERN ARMY WARNING
Not far from the explosions, tens of thousands of red-shirted supporters of former prime minister Thaksin Shinawatra have fortified their redoubt in a Bangkok commercial district with home-made barricades, expecting the army to evict them any time.
The army earlier on Thursday warned it would forcibly disperse the mostly rural and urban poor protesters who have set up a self-contained village in a roughly 3 square-km (1.9 mile) area of an upscale shopping and hotel area in central Bangkok.
"Your days are numbered," Sansern said earlier on Thursday.
Any attempt to disperse them risks heavy casualties and the prospect of clashes spilling into high-end residential areas. But Deputy premier Suthep Thaugsuban said there would be no crackdown Thursday night because women and children were in the area.
He said three people were killed in the blasts. The health ministry said 75 were wounded.
Leaders of the red shirted supporters of twice-elected and now fugitive Thaksin say they will only leave when the military-backed government announces early elections.
They say the British-born, Oxford-educated Prime Minister Abhisit Vejjajiva came to power illegitimately, heading a coalition the military cobbled together after courts dissolved a pro-Thaksin party that led the previous coalition government.
Analysts say the protests are radically different from any other period of unrest in Thailand's polarizing five-year political crisis -- and arguably in modern Thai history, pushing the nation close to an undeclared civil war.
They have evolved into a dangerous standoff between the army and a rogue military faction that supports the protesters and includes retired generals allied with Thaksin, who was ousted in 2006 coup and later convicted of breaching conflict-of-interest laws and sentenced in absentia to two years in prison.
"MULTI-COLOUREDS" TO RALLY
A pro-government group said earlier it plans to gather 50,000 people for a rally on Friday outside the prime minister's office in central Bangkok to voice opposition to the red shirts, splitting the capital into opposing groups and heightening the risk of clashes.
An official close to the prime minister cast doubt on the idea of an imminent crackdown, conceding civilian casualties would be too high. The standoff could last weeks, he said.
"This could go on for some time," he told Reuters.
The red shirt uprising showed the first signs of spreading beyond Bangkok to the protesters' stronghold in the northeast after they blocked a train carrying troops and military vehicles.
In the province of Khon Kaen, about 400 km (249 miles) from Bangkok, red shirts agreed on Thursday to let a military train proceed -- if it takes along 10 of them to ensure it goes to its intended destination in southern Thailand and not bring reinforcements to Bangkok.
About 200 red shirt protesters rallied in front of the regional headquarters of the United Nations in Bangkok on Thursday requesting peacekeepers be deployed to provide security. Police made no move to stop them.
The crisis has decimated Thailand's important tourism industry and was cited as one reason the central bank left interest rates at a record low on Wednesday.
But Thailand's exports jumped 41 pct year-on-year in March, compared to 23 percent in February, indicating the protests have yet to punish the wider economy.
(Additional reporting by Nopporn Wong-Anan; Writing by Jason Szep; Editing by Bill Tarrant)