BANGKOK: Anti-government protesters massed in the Thai capital Saturday vowing to keep up their fight to topple the government, a day after a bomb attack on their rally that killed one and wounded dozens.
Tensions in Bangkok soared following the blast, the latest bloodshed in weeks of demonstrations aimed at forcing Prime Minister Yingluck Shinawatra from office and derailing February 2 elections.
A 46-year-old protester who died of his wounds from the explosion became the ninth person killed during the demonstrations, which have also seen scores injured in several outbreaks of unrest.
Thousands marched without incident in the centre of the city on Saturday, waving Thai national flags and blowing their trademark whistles.
"We have to go on with our fight because what we are doing is for our country," rally leader Suthep Thaugsuban told reporters before embarking on the march, although he added the movement was on "full alert".
Suthep was nearby when the explosion tore through Friday's march as protesters neared a busy intersection in the shopping district of the city.
The capital's Erawan emergency centre said the blast left one dead and 37 injured, with 11 remaining in hospital.
An official from the centre said the injured protester died of his wounds early Saturday.
"He died from severe loss of blood after suffering shrapnel wounds to his major internal organs," the official told AFP.
Both authorities and demonstrators blamed each other for the blast, which was apparently caused by a grenade-type device thrown from a nearby building.
Thailand has been periodically rocked by bouts of bloody unrest since just before a 2006 military coup that ousted Thaksin Shinawatra -- Yingluck's older brother -- who now lives in self exile abroad to avoid a jail term for corruption.
The current wave of protesters is made up of a coalition of Thaksin's foes among the Bangkok middle class, southerners and the royalist elite.
They want to rid the kingdom of the influence of the former leader and are calling for an unelected "people's council" to push through vaguely defined reforms before an election in a year or more.
Demonstrators have occupied major intersections in the capital since Monday in what they have dubbed the "Bangkok shutdown".
Authorities said some two thousand protesters were briefly permitted to rally in the grounds of the national police headquarters on Saturday calling for officials to arrest those responsible for Friday's attack.
"I worry about this government, that they will do anything to stop us, but no one can stop us," protester Tu Prapaiporn told AFP.
The rallies were triggered by a failed amnesty bill that could have allowed Thaksin to return without going to jail.
The billionaire telecoms tycoon-turned-politician is accused of controlling his sister's government from his base in Dubai.
He has strong electoral support in northern Thailand, which has helped him and his allies win every election in Thailand this century.
Yingluck called the snap February poll in an attempt to deflate the political crisis, but the main opposition Democrat Party is boycotting the polls, fearing they would again lose to the Shinawatra family.
Thailand is no stranger to political upheaval and has seen 18 actual or attempted coups since 1932, while the judiciary has also stepped in to strip pro-Thaksin governments of power in the past.
Government supporters fear the protest violence is aimed at provoking another military coup, although the army has so far seemed reluctant to pursue this option.
"It is the last gasp for Suthep and his protesters," said Thida Thavornseth, head of the largely pro-Thaksin Red Shirt movement.
Yingluck is facing several legal moves which experts say could potentially bring down her government.
On Thursday the National Anti-Corruption Commission launched an investigation into possible negligence of duty by Yingluck in connection with a controversial subsidy scheme for rice farmers.
The government has urged police to detain Suthep, who faces an insurrection charge -- in theory punishable by death -- in connection with the protests.
The political unrest is the worst seen in the country since 2010 Red Shirt protests that ended with a bloody military assault on demonstrators and left over 90 dead and 1,900 wounded.
Suthep, who was the Democrat deputy prime minister at the time, faces a murder charge over the crackdown.