Tens of thousands of monks and civilians in Burma's main city Rangoon have defied military warnings and staged new anti-government protests.
Some chanted "we want dialogue". Others simply shouted "democracy, democracy".
Earlier, lorries with loudspeakers warned residents that the protests could be "dispersed by military force".
After the march finished, eyewitnesses told two news agencies they had seen several military trucks moving on Rangoon's streets.
1. Shwedagon Pagoda. Tens of thousands of protesters, led by monks, gathered here at start of march
2.Sule Pagoda. Students joined the protest, passing nearby city hall
Reuters reported that eight trucks carrying armed riot police and 11 carrying troops had moved into the city centre.
The security forces stayed in the vehicles while a few hundred people looked on, AFP said.
Tens of thousands of monks and supporters had earlier marched from Shwedagon pagoda into the commercial centre of Rangoon, where they gathered around Sule pagoda and nearby city hall, witnesses told AFP.
Protesters addressed the crowd outside city hall.
"National reconciliation is very important for us... The monks are standing up for the people," proclaimed poet Aung Way.
One monk told the Associated Press: "People do not tolerate the military government any longer."
The BBC's Jonathan Head in Bangkok says monks - who have been spearheading the protest campaign - have been handing out pictures of Burmese independence hero Aung San, the deceased father of detained opposition leader Aung San Suu Kyi.
They were also carrying flags, including some bearing the image of a fighting peacock used by students during the 1988 pro-democracy uprising, witnesses told Reuters.
Students were also openly marching, says the BBC Burmese Service. In earlier marches they had simply formed a chain and clapped.
15 Aug: Junta doubles fuel prices, sparking protests
5 Sept: Troops injure several monks at a protest in Pakokku
17 Sept: The junta's failure to apologise for the injuries draws fresh protests by monks
18-21 Sept: Daily marches by monks in Burmese cities gradually gather in size
22 Sept: 1,000 monks march to the home of Aung San Suu Kyi in Rangoon
23 Sept: Up to 20,000 march in Rangoon
24 Sept: New Rangoon march draws at least 50,000 and 24 other towns join in
"Some students are in the middle of exams at this time," one of the students told the BBC. "But they have left their exam rooms and come out onto the streets, joining hands with the public, fighting for the country under the guidance of the monks."
The junta, which violently repressed the 1988 protests killing some 3,000 people, finally broke its silence over the mounting protests late on Monday, saying it was ready to "take action" against the monks.
It repeated the warning on state media, ordering monks not to get involved in politics and accusing them of allowing themselves to be manipulated by the foreign media.
At the opening of the UN General Assembly in New York, Secretary General Ban Ki-moon urged Burma's rulers to exercise restraint in the face of the growing protests.
US President George W Bush is to use his speech - due shortly - to announce further sanctions against Burma's ruling military junta, the White House has said.
The US is hoping it will encourage other nations to act and embolden the protesters on Burma's streets, says the BBC's Jonathan Beale in Washington.
Close neighbour China called for "stability", and the European Union has also urged the junta to show the "utmost restraint" and to take the opportunity to "launch a process of real political reform".
The exiled Tibetan spiritual leader, the Dalai Lama, has given his backing to the monks' call for freedom and democracy.
The protests were triggered by the government's decision to double the price of fuel last month, hitting people hard in the impoverished nation.
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