Updated

Venezuelan President Hugo Chavez hinted Friday that the U.S. may be behind several cases of cancer affecting South American leaders, including his own, and called the situation "very strange."

According to Bloomberg Businessweek, Chavez, a frequent critic of the U.S., said in a nationally televised speech to the military, "It's very difficult to explain, even with the law of probabilities, what has been happening to some of us in Latin America.

"Would it be so strange that they've invented technology to spread cancer and we won't know about it for 50 years?"

Chavez was diagnosed with cancer last June and has been traveling to Cuba for treatment and chemotherapy.

On Tuesday, Argentine President Cristina Fernandez de Kirchner was diagnosed with thyroid cancer. Other South American leaders who have battled the disease are Brazilian President Dilma Rousseff, her predecessor Luiz Inacio Lula Da Silva and Paraguay's Fernando Lugo.

"I'm just sharing my thoughts, but it's very, very, very strange," Chavez said, according to Bloomberg Businessweek. "Evo take care of yourself, Correa, be careful, we just don't know" - a reference to Evo Morales and Rafael Correa, the leaders of Bolivia and Ecuador.

Chavez also said that his close friend, former Cuban leader Fidel Castro, had warned him, "Chavez be careful, they've developed technology, be careful with what you eat, they could stick you with a small needle."

Bloomberg Businessweek reported Chavez said he wasn't accusing anyone, "just using my freedoms to reflect and issue comments on very strange events that are hard to explain."