At least 30,000 Thai "Red Shirts" gathered in Bangkok on Sunday, police said, in their biggest show of strength since a deadly military crackdown on their mass anti-government protest last year.
The demonstrators, clapping and singing in their trademark red clothes, brought traffic to a standstill in parts of the capital as they marched to the upscale shopping district calling for the release of their leaders in jail.
A security force of 1,000 was deployed in the capital for the event - the Red Shirts' first Bangkok rally since emergency rule was lifted there last month.
Police Major General Piya Utayo of the Metropolitan Police told AFP that 30,000 Reds had gathered, while a special branch police source later said as many as 40,000 people were present at the protest's peak.
Red Shit hero former prime minister Thaksin Shinawatra, ousted in a military coup in 2006, and whoe lives abroad to escape a jail term for corruption, addressed demonstrators in a ten minute phone-in to the rally.
Shinawatra addressses crowd via phone
"I admire you for having strong hearts for democracy. The government's meaning of reconciliation is to chase up people who they can arrest, so that that the Reds will be no more," he told the crowds.
The controversial Thaksin, who draws support among the mainly poor and working class Red Shirts but is hated by the urban elite, said he was making the call from "a plane flying over Europe".
The Red Shirts have vowed to hold rallies twice a month in Bangkok to secure the release of their leaders who were jailed after their protest in April and May last year, which saw more than 90 people killed in clashes with troops.
"I'm doing my best to call for the release of people jailed and to remember those who lost their lives," said Jatuporn Prompan, a lawmaker and one of the senior Red Shirts facing terrorism charges.
Jatuporn, who has been granted bail, said legal experts had told him he could take part in the protest without violating his bail conditions so long as he did not speak to the crowds.
Sunday's rally comes as Prime Minister Abhisit Vejjajiva -- whose term runs out at the end of this year -- announced a new welfare package, which is designed to help low-income groups and address social inequalities.
The Red Shirts' two-month rally last year, which attracted 100,000 people at its peak in support of their demand for immediate elections, was brought to a bloody end on May 19 with a military assault on the group's base.
After the crackdown, a small band of militant protesters set dozens of buildings ablaze across Bangkok, including a glitzy shopping mall.
The group has since staged several rallies in the capital, the last attracting around 10,000 people on December 19, despite a state of emergency banning gatherings of more than five people, which was lifted late last month.
On Saturday a bomb in the Thai northeast, the Red Shirts' heartland, damaged a school named after the king's top aide but caused no injuries.
The bomb damaged the library at the school named after General Prem Tinsulanonda, the head of the king's privy council and a former prime minister whom the Red Shirts believe masterminded the coup that deposed Thaksin.
An intelligence official said the attack seemed designed to cause political unrest.
