middle of a four-lane highway leading to Sule Pagoda -- the end-point of mass demonstrations this week and now locked.
More than 1,000 people surrounded them as riot police watched from behind their shields, witnesses said.
It was not immediately clear how many more of the revered, maroon-robed monks who have led the mass protests would turn up or how many ordinary people would dare demonstrate after pre-dawn raids on rebellious monasteries.
Ignoring increasingly desperate international calls for restraint, the generals sent troops into monasteries in Yangon and elsewhere and took several hundred monks away in trucks.
But fears grew of a repeat of 1988, when troops killed an estimated 3,000 people in the ruthless suppression of a nationwide uprising.
As security forces set up barbed-wire barricades at major junctions in central Yangon, monks on Burmese-language foreign radio stations urged their comrades not to surrender.
"We would like to call on the student monks to keep on struggling peacefully," one protest leader said on the BBC service. "Five monks have sacrificed their lives for our religion."
Barricades sealed off the gilded Shwedagon Pagoda, the country's holiest shrine and start-point for more than a week of monk-led protests. The only people were a woman selling fruit and German tourists trying to see the sights, a witness said.
Troops and police also stationed seven fire engines to be used as water cannons near the Sule Pagoda. The gates of the downtown temple were locked, and armed police waited inside.
Raids fuel anger
The monastery raids were likely to inflame the former Burma's 56 million people, already fed up with 45 years of unbroken military rule and economic hardship.
"Doors of the monasteries were broken, things were ransacked and taken away," a witness said. "It's like a living hell seeing the monasteries raided and the monks treated cruelly."
People living near Yangon monasteries, the revered moral centre of the Buddhist nation, reported that at least 500 monks were taken away in army trucks.
They were taken during the second night of a dusk-to-dawn curfew from monasteries believed to be coordinating protest marches, monks said.
Several monasteries in the remote northeast were also hit and monks carted off. "Only two or three sick monks were left behind," a person living hear the Ngwe Kyaryan monastery said.
Facing the most serious challenge to its authority since 1988, the junta admitted one man was killed and three wounded when soldiers fired warning shots and tear gas at crowds on Wednesday.
Protest leaders said at least five monks were killed as soldiers and riot police tried to disperse the biggest crowds in a month of marches against grinding poverty.
Overnight, police arrested two senior members of the opposition National League for Democracy (NLD), the party's spokesman said. Two opposition politicians from other parties were also detained.
China says "no" to sanctions
The international outrage at Wednesday's use of warning shots, tear gas and baton charges against monks and unarmed civilians was loud by any standards.
U.S. Secretary of State Condoleezza Rice called it a "tragedy" and urged the generals to allow a U.N. envoy to visit and meet detained pro-democracy leader Aung San Suu Kyi.
"The regime has reacted brutally to people who were simply protesting peacefully," Rice said on the sidelines of the U.N. General Assembly in New York.
U.N. Secretary-General Ban Ki-moon said he would dispatch special envoy Ibrahim Gambari to Southeast Asia in hope the hope that the generals would let him in.
However, in a sign of rifts within the international community at an emergency meeting of the UN Security Council in New York, China ruled out sanctions or an official condemnation of the use of force.
History suggests the junta will not be moved by threats from France and Britain -- former imperial powers -- that leaders would be held responsible for bloodshed. British Prime Minister Gordon Brown said the "age of impunity" was over.
The United States and the 27-nation European Union called on the generals to start a dialogue with pro-democracy leaders, including Nobel laureate Suu Kyi, and ethnic minority groups.
Foreign ministers of the Group of Eight industrial nations agreed on a similar formula but without a call for sanctions, in deference to Russia.
Participants said Rice and Russian Foreign Minister Sergei Lavrov, whose country has sided with China in blocking U.N. moves against Myanmar, clashed over the sanctions issue.
Washington and Paris called on China to use its influence to convince the junta to stop the crackdown.
Diplomats say China has privately been speaking with the Myanmar generals to convey international concern, but Beijing has so far refrained from any public criticism.