CARACAS (CBSMiami) – US President Donald Trump tweeted Tuesday afternoon a stern warning to Cuba over its involvement in Venezuela.

This was the president’s tweet: “If Cuban Troops and Militia do not immediately CEASE military and other operations for the purpose of causing death and destruction to the Constitution of Venezuela, a full and complete embargo, together with highest-level sanctions, will be placed on the island of Cuba. Hopefully, all Cuban soldiers will promptly and peacefully return to their island!”

Secretary of State Mike Pompeo said that embattled Venezuelan leader Nicolas Maduro was preparing to leave the country for Cuba, but was talked out of it by Russia.

“We’ve watched throughout the day, it’s been a long time since anyone’s seen Maduro,” Pompeo said in an interview with CNN’s Wolf Blitzer.

“He had an airplane on the tarmac, he was ready to leave this morning as we understand it and the Russians indicated he should stay.”

“He was headed for Havana,” Pompeo said.

Pompeo said in a tweet Tuesday morning, “Today interim President Juan Guaidó announced start of Operación Libertad (Operation Liberty). The U.S. Government fully supports the Venezuelan people in their quest for freedom and democracy. Democracy cannot be defeated.”

Thousands of Venezuelans hit the streets Tuesday after Guaidó declared “the start of the end of the usurpation.”

In a dawn address, Guaidó addressed the nation through his Twitter account to call for all Venezuelans to take to the streets. He was flanked by men in military fatigues and armored vehicles in the capital of Caracas.

Guaidó, who is head of Venezuela’s national assembly and has been recognized as president by more than 50 countries, had originally called for a massive May 1st day of demonstrations but moved the planned action for Tuesday.

He said ‘Operation Liberty’ had begun.

Many analysts were calling this the beginning of the end for the Maduro regime.

SEE PHOTOS FROM TUESDAY’S CLASHES

Video images from Caracas showed Maduro forces repressing street protesters with tear gas. One scene showed a military armored vehicle ramming into a crowd of civilian protesters.

Maduro’s top general Vladimir Padrino Lopez took to the airwaves to say the Venezuelan military stands with Maduro.

The surprise rebellion had only managed to garner limited military support.

Maduro’s government, working with foreign advisers, had blocked internet access, according to local sources. It is not the first time Maduro blocks such access to the masses.

PRESIDENT TRUMP ISSUES STERN WARNING TO CUBA:

On Tuesday morning, Guaidó tweeted:

“People of Venezuela, it is necessary that we take to the streets to support the democratic forces and to recover our freedom. Organized, let’s all together head to the main military bases. Residents of Caracas, let’s all go to the Carlota (Military base).”

White House National Security Adviser John Bolton urged the Venezuelan Armed Forces to defend legitimate institutions against the usurpation of democracy.

Bolton repeated the US stance vis-a-vis Venezuela in that “all options are on the table,” during an afternoon press conference at the White House.

Meanwhile, longtime supporter of freedom in Venezuela, US Senator Marco Rubio tweeted, “This is the moment for those military officers in #Venezuela to fulfill their constitutional oath & defend the legitimate interim President @jguaido in this effort to restore democracy. You can write history in the hours & days ahead.”

Later in the day, Guaidó made his way to Plaza Altamira, the center of the city’s opposition heartland. “For many years we have talked to the armed forces and today it’s clear to us that the armed forces are with the Venezuelan people, who are not with a dictator,” Guaido told a heaving crowd of supporters, who were cheering “Yes, we can.”

Using a megaphone, the 35-year-old said the demonstration was peaceful, “in accordance with our constitution,” and it was Maduro who was carrying out a coup.

“The coup d’etat is being done at a stage by those who use paramilitaries to attack us. The soldiers are here to defend our people,” he added.

Earlier, Guaidó had told CNN that Maduro had lost the support of the country’s military. “It’s great news for the entire country that the military of Venezuela’s armed forces have taken this step. They were an important part of this. This was fundamental not only for a transitioning, but to recover Venezuela’s sovereignty,” he said.

Late Tuesday night, Maduro tweeted a video showing him speaking to supporters on television.

In it, he describes the protests as small. In another tweet he said he still has the support of military commanders.

The Venezuelan government has also stopped airing CNN and BBC news.

On Tuesday morning, US Vice President Mike Pence tweeted his support for Guaidó:

To @jguaido, the National Assembly and all the freedom-loving people of Venezuela who are taking to the streets today in #operacionlibertad—Estamos con ustedes! We are with you! America will stand with you until freedom & democracy are restored. Vayan con dios! #FreeVenezuela — Vice President Mike Pence (@VP) April 30, 2019

(©2019 CBS Broadcasting Inc. All Rights Reserved. Cable News Network, Inc., a Time Warner Company, contributed to this report.)