Tens of thousands of Venezuelans have marched in support of a private television station that is being forced off the air Sunday by the nation's government. In Caracas, VOA's Brian Wagner reports security forces have deployed in the capital and other opposition-led regions to guard against possible violence.

Protesters marched to the headquarters of Radio Caracas Television, denouncing plans by the government to strip the broadcasting license from the nation's oldest private television station. Supporters placed black tape and bandanas over their mouths and carried signs that read "No to silence" during the march in downtown Caracas. Pro-government supporters elsewhere in the city held a smaller rally to praise the decision.

Critics accuse the government of refusing to renew the broadcast license of RCTV, which expires Sunday, in an effort to silence opposition views.

Officials have defended the decision against RCTV, which it accuses of airing indecent programs and of backing a 2002 coup against President Chavez. RCTV executives deny the coup charges, and accuse the president of building a totalitarian regime.

Opinion polls have shown that the decision against RCTV is unpopular among Venezuela's population, despite strong support in general for President Chavez.

Zulia state Governor Manuel Rosales, a key opposition leader, said the government is seeking greater control over the nation's airwaves.

Rosales says the government took over RCTV, in violation of the station's private property rights, in order to gain a new media outlet with broad reach.

At the inauguration of a health clinic on Saturday, President Chavez defended the decision, saying the government has renewed the licenses of dozens of other private television and radio outlets.

President Chavez says says RCTV became a threat to the nation and its children, and he made the decision to end its broadcasting license. Mr. Chavez also warned of possible efforts to sabotage the new public channel, and he said security forces are prepared to respond.

Venezuelan army tanks and security forces deployed across the capital and other cities ahead of the protests, which are expected to continue Sunday.

Army General Juan Paredes Torrealba said the military is authorized to guard against possible violence. He says they are not expecting disorder or disturbances from small groups of people, but if there is trouble, the armed forces are prepared to act.

International human rights groups and press freedom organizations have condemned the expiration of RCTV's license as a blow to free speech in Venezuela. Friday, U.S. senators unanimously approved a resolution expressing profound concern at what they called the "transgression against freedom of thought and expression."

Venezuela's supreme court has authorized the government to take control of RCTV broadcasting equipment as part of the transfer of control. The court has rejected a legal challenge by the station, which sought to delay the transfer while the court reviews the government's decision.

Meanwhile, RCTV has continued with much of its regular programming, which includes several popular soap operas, comedy shows and news programs. Officials say after midnight Sunday, the channel will be renamed Venezuelan Social Television and air public interest programs.