Updated

CARACAS, Venezuela (AP) — It's no longer just doctors, nurses and teachers. Cuba now sends Venezuela troops to train its military, and computer experts to work on its passport and identification-card systems.

Critics fear that what is portrayed by both countries as a friendship committed to countering U.S. influence in the region is in fact growing into far more. They see a seasoned authoritarian government helping President Hugo Chavez to protect his power through Cuban-style controls, in exchange for oil. The Cuban government routinely spies on dissidents and maintains tight controls on information and travel.

Cubans are involved in Venezuelan defense and communications systems to the point that they would know how to run both in a crisis, said Antonio Rivero, a former brigadier general whose break with Chavez over the issue has grabbed national attention.

"They've crossed a line," Rivero said in a May interview. "They've gone beyond what should be permitted and what an alliance should be."

Cuban officials dismiss claims of outsized influence, saying their focus is social programs. Chavez recently scolded a Venezuelan reporter on live television for asking what the Cubans are doing in the military.

"Cuba helps us modestly with some things that I'm not going to detail," Chavez said. "Everything Cuba does for Venezuela is to strengthen the homeland, which belongs to them as well."

But the communist government has a strong interest in securing the status quo because Venezuela is the island's principal economic benefactor, Rivero says.

As Cuba struggles with economic troubles, including shortages of food and other basics, $7 billion in annual trade with Venezuela has provided a key boost — especially more than 100,000 barrels of oil Chavez's government sends each day in exchange for services.

Rivero, who retired early in protest and now plans to run for a seat in the National Assembly, said Cuban officers have sat in high-level meetings, trained snipers, gained detailed knowledge of communications and advised the military on underground bunkers built to store and conceal weapons.

"They know which weapons they have in Venezuela that they could count on at any given time," he said.

Cuban advisers also have been helping with a digital radio communications system for security forces, meaning they have sensitive information on antenna locations and radio frequencies, Rivero said.

If Chavez were to lose elections in 2012 or be forced out of office — like he was during a brief 2002 coup — it's even feasible the Cubans could "become part of a guerrilla force," Rivero said. "They know where our weapons are, they know where our command offices are, they know where our vital areas of communications are."

Chavez has acknowledged that Cuban troops are teaching his soldiers how to repair radios in tanks and to store ammunition, among other tasks. No one complained years ago, he added, when Venezuela received such technical support from the U.S. military.

Cuba and Venezuela are so unified that they are practically "one single nation," says Chavez, who often visits his mentor Fidel Castro in Havana and sometimes flies on a Cuban jet.

The countries plan to link up physically next year with an undersea telecommunications cable. The Venezuelans are even getting advice from President Raul Castro's daughter Mariela Castro, who heads Cuba's National Sex Education Center and advocated civil unions for homosexuals during a recent seminar in Caracas.

Some Venezuelans mockingly call it "Venecuba." When the government took over the farm of former Venezuelan U.N. ambassador Diego Arria, he contested the seizure by delivering his ownership documents to the Cuban Embassy, saying the Cubans are in charge and "much more organized than the Venezuelan regime."

"No self-respecting country can place such delicate areas of the government as national security in the hands of officials of another country," said Teodoro Petkoff, an opposition leader who is editor of the newspaper Tal Cual. "President Chavez doesn't trust his own people very much. So he wants to count on the know-how and time-tested experience of a government that for 50 years has been carrying out a brutal and totalitarian dictatorship."

Cuban government officials, however, say the bulk of their assistance is in public services.

At the National Genetic Medicine Center in Guarenas, east of Caracas, Cuban doctors and lab technicians diagnose and treat genetic illnesses.

"What we came to do is science," said Dr. Reinaldo Menendez, the Cuban director of the center, which also employs Venezuelans. "Our weapons... are our minds, our work, our coats, our stethoscopes.

"We're internationalists by conviction," he added, passing photos of Chavez and Fidel Castro on the walls.

Cuban Deputy Health Minister Joaquin Garcia Salavarria coordinates missions involving more than 30,000 doctors, nurses, and other specialists from the island. He estimated that about 95 percent of the approximately 40,000 Cubans in Venezuela work in medical, education, sports and cultural programs, and that others are helping as advisers on everything from agriculture to software for the state telephone company, CANTV.

As he spoke, Garcia flipped through a file of statistics that he said show the real impact of the Cuban presence: more than 408 million consultations in neighborhood health clinics since 2003. That's an average of 14 medical visits for each of Venezuela's more than 28 million people.

Many Venezuelans are grateful for the free medical care provided by the Cubans, and waiting rooms are often bustling. Still, polls have repeatedly shown a large majority of Venezuelans don't want their country to adopt a system like Cuba's.

Chavez says he's not copying Cuba's socialist system but has adopted some practices, like creating a civilian militia to defend his government. When he founded a fledgling national police force last year, Chavez boasted that "we're going to compete with the Cuban police force, which is among the best in the world."

A senior Cuban police official, Rosa Campoalegre, has been in Caracas to help with plans for a new university for police and other security officials. She declined a request to be interviewed.

Cuban experts have also been working on systems in public registries and notaries. About 12 Cuban computer specialists from the University of Computer Science in Havana have been creating software to help the immigration agency improve passport control and computerize the identification card system, director Dante Rivas said.

"There's nothing to hide here," Rivas said. "What they do is develop the software, jointly with us, but we operate it exclusively. That's all. They don't do anything else."

In Cuba, he said, the government uses a different system.

The island's computerized civil registry includes all relevant data on its citizens, such as address, age and physical characteristics. All Cubans must carry an identity card, and those who want to travel outside the country must get special permission.

It's especially worrying that Cubans are involved in areas "that have to do with control of information, people's private information," said Rocio San Miguel, who heads a Venezuelan organization that monitors security and defense issues.

Chavez, meanwhile, says Cuba's assistance is worth "10 times more than the cost of the oil we send."

He has effusively thanked Cuba for helping Venezuela to revamp its electrical system — a move ridiculed by Chavez's opponents due to Cuba's own struggles with power outages. Chavez also credited a Cuban cloud-seeding program with helping to bring an earlier rainy season this year after a severe drought.

"What Cubanization?" he said. "The Cubans are helping us."