BEIJING -- China declared martial law in Beijing Saturday and launched a wide crackdown on a massive popular uprising, sending out troops armed with assault rifles. Scattered clashes were reported throughout the city.
Unconfirmed reports said Communist Party chief Zhao Ziyang resigned from his post because of his reported disagreement with China's leadership over the handling of the protests.
At least 45 students were injured in the worst of these clashes, in Fengtai on the city's southwestern outskirts, witnesses said, when paramilitary police and troops broke through lines of protesters trying to block their path.
Several students staggered into Tiananmen Square with bloodied shirts and faces and claimed to have been beaten by police or troops in confrontations at various points around the city.
The municipal government Saturday restricted the activities of Chinese and foreign journalists, forbidding them from news gathering in most public areas. The transmission lines of United Press International and other wire services were cut temporarily following government warnings about coverage. They were restored Saturday.
The moves were aimed at stopping continued mass protests but often had the opposite impact as hundreds of thousands of people jammed the streets, some heading toward Tiananmen Square, the main site of four days of massive student-led protests for freedom.
The square was filled with college students who were still streaming into the capital from throughout the nation, filling trains and clogging the roads to Beijing.
The crowds in the square passed out towels to protect themselves from expected tear gas assaults, witnesses said.
The popular uprising had left the Chinese leadership with its worst political and civil crisis since the 1966-76 Cultural Revolution. Since mid-April, pro-democracy demonstrations have broken out in virtually every major city in China for the first time since the founding of the communist state in 1949.
Premier Li Peng, in a speech to party and government leaders broadcast early Saturday on national television, sternly called for 'resolute and powerful measures to curb turmoil and restore order.'
Zhao did not appear on the broadcast and was said by Chinese sources to have suffered a loss of power over differences with other leaders on the decision to call out the army.
Zhao, who has been the most conciliatory leader since student protests erupted a month ago, was said to to have submitted his resignation to Politburo's ruling Standing Committee, of which he is one of five members.
Chinese sources said the other four members, including Li, initially refused to accept it, but determined that Zhao should lose power as he refused to accede to the government's preparations to use force if necessary to end the student protests.
There was no official confirmation of the report.
On Friday, Zhao made an emotional appeal to hunger-striking students in Tiananmen to end their strike and signed autographs.
An announcement Saturday by the State Council, China's Cabinet, declared all the capital's eight urban districts, including the foreign embassy quarters and the university areas, under martial law 'to firmly stop the unrest.'
The imposition of martial law came after thousands of people formed a virtual citizens' army Friday night and blocked roads to prevent large numbers of troops from reaching Tiananmen square.
Soon after, an American television crew saw police near the square beat protesters with billy clubs. More scuffling broke out as police tried to remove student barricades.
Most of the clashes occurred as a truckloads of soldiers, armed with AK-47 automatic rifles attempting to make their way through the city, confronted large crowds of angry demonstrators.
Police at times used truncheons and electric prods on protesters, witnesses said.
The capital had erupted in raucous but peaceful revolt as thousands of people took to the streets. Steelworkers, students, grandmothers and children surrounded troop convoys and formed human barricades or used vehicles to stop them.
'Let them come, let them shoot, we don't care,' shouted a driver from one of three dump trucks parked across Changan Avenue, the major east-west artery, in a 1-mile stretch where three such barricades were set up.
To the city center's north, workers knelt in front of huge green troop trucks filled with stony-faced soldiers and slashed the tires, said Alexis Feringa, an American student. On the east, students commandeered buses and parked them at a main intersection, stalling another convoy.
On the west, crowds linked arms across Fuxing Avenue to keep a parked convoy from moving, crying 'don't do this.'
An angry middle-aged woman climbed aboard a truck and spat at the soldiers: 'Where's your conscience?'
Witnesses said some of the soldiers, recruits still in their teens, covered their faces with their hands and appeared near tears.
In the northwest university district, troops tried to move onto the campus of People's University, but the demonstrators slammed the university's gates on them and the troops did not use force, students reached by phone said.
Although the crowds have been peaceful and there had been no anti-foreign sentiment, the goverment move to call out the troops has sent shivers through the city's foreign community.
The U.S. Embassy issued a warning to residents to avoid going out after dusk and to carry proper identification. The warning also advised Americans to observe laws and regulations set out in the martial law decree.
The British, Canadian and Australian embassies also issued advisories to their nationals to stay inside, at least temporarily.
The British Embassy urged those with travel plans for China 'to reconsider.' A spokesman said, 'The answer for residents is to keep one's head down.'
The official Chinese Xinhua news agency said the decision 'to execute martial law' came because 'social stability, people's normal lives and social order have been disrupted.'
The announcement said the areas would be controlled by soldiers, that demonstrations would be banned and that anyone in the areas would be required to produce identification on demand.
The White House urged restraint on the part of the Chinese government.
'This evening's events in China appear confused, but both sides have exercised restraint. We hope this will continue,' said White House spokesman Marlin Fitzwater.
'The announcement of a news blackout is very disturbing and we urge that it not signal an end to appropriate restraint or an end to dialogue with the students.'
The order restricting news coverages reflects serious concern over reporting by foreigners and a revolt against censorship among Chinese journalists that has accompanied the growing demonstrations.
The government also informed American television networks they would no longer be able to use private satellite transmission stations and forced the Cable News Network to cut live broadcasting.
The final moments of CNN's live broadcast showed network officials negotiating in vain with Chinese officials.
However, network spokesmen said they were told networks could still transmit via Chinese government television facilities, subject to the availability of time and space.