CARACAS, Venezuela: President Hugo Chavez's continued silence in the week since his return to Venezuela has only deepened the mystery about his health.

While tweets and letters have been issued in Chavez's name, and officials insist they have had long meetings with him, no photos have emerged and even an ally as close as Bolivian President Evo Morales was turned away without a bedside meeting.

Some Venezuelans have questioned whether the socialist president is at a military hospital in Caracas at all, whether he even returned from Cuba or whether he is in fact still alive. Many Venezuelans say they no longer know what to believe.

Chavez hasn't spoken publicly since before his Dec. 11 surgery in Cuba, perhaps because of a breathing tube, and he has been seen only in a handful of photographs that the government released on Feb. 15. They showed Chavez smiling as he reclined in a bed, with two of his daughters beside him.

The lack of images or messages has been a stark change for a leader who used to speak on television almost every day for hours at a time.

Opposition newspaper editor Teodoro Petkoff said Chavez's post-return invisibility has ratcheted up the surreal nature of a situation that he called "politically Kafkaesque."

"The president returned from Cuba, but not a few people think he remains there, given that the practice of keeping him invisible was moved from the island to his own land," Petkoff wrote in an editorial published Tuesday in the newspaper Tal Cual.

Waves of rumors have swept the nation since Chavez first announced in June 2011 that he had a cancerous tumor removed from his pelvic region during an operation in Cuba. Posts on Twitter, gossip in the street and the occasional newspaper story have ranged from claims of Chavez's death to accounts that he had suffered a heart attack or slipped into a coma. The government has repeatedly dismissed such suggestions as fabrications, but has given only patchy accounts itself of the president's condition or treatment. Chavez himself asserted he was free of cancer last year, only to return for a new operation within months.

On Friday, speculation flew on Twitter that some in the military were rising up against Vice President Nicolas Maduro. Some speculated that Maduro's appearance on television that night was intended in part to calm the rumors, which apparently also prompted Defense Minister Diego Molero to issue a message on his ministry's Twitter account the next day, reiterating that the armed forces remains unified behind Chavez's government.

Newspaper columnist Nelson Bocaranda, who has published many reports about Chavez's condition, reported at one point last week that Chavez wasn't in the Dr. Carlos Arvelo Military Hospital as officials say but was instead at the Fort Tiuna military base.

National Assembly president Diosdado Cabello said Monday that critics were "trying to create anxiety."

"They blatantly lie," said Cabello, a close Chavez confidant. He scolded some for claiming "it's a lie that Chavez is there in the military hospital."

Cabello is one of the few government officials who say they have met with Chavez at the military hospital where they say he is receiving treatment both for his cancer and for a persistent "respiratory insufficiency."

Maduro has said the 58-year-old president has been breathing through a tracheal tube that hinders speech, but that he is able to communicate through writing and that he met with aides for about five hours last week.

Also last week, Foreign Minister Elias Jaua read a lengthy letter from Chavez to a gathering of African and South American leaders. On Monday, the government issued a message of congratulations from Chavez to Cuban President Raul Castro after he was re-elected by lawmakers.

Still, doubts, speculation and contradictory accounts regarding Chavez's whereabouts and his health have reached such proportions that sociologist Tulio Hernandez calls the phenomenon "collective hallucination."

While many believe the president is completely bedridden, at least a few claim they have sighted him - reports that officials have not confirmed.

Kirya Ramos, an employee at the state-run National Nutrition Institute, told The Associated Press that she caught a glimpse of Chavez when he arrived before dawn on Feb. 18 at Simon Bolivar International Airport, near her home in coastal Vargas state.

"There was such a ruckus in Vargas," when he returned from Cuba, Ramos said, that she and others went to see. She said they spotted the plane.

"We saw when Chavez came down the stairs," Ramos said.

On the day of his return, state television broadcast comments by a woman identified as a hospital employee who said she watched Chavez stroll into the hospital.

"A country in which some people see the president and others do not see him is obviously in a state of collective hallucination," said Hernandez, a government critic. "He built his own image. He constructed his own myth, and he will be sitting to the right of Che Guevara as long as Latin American revolutionary mythology exists."

Sociologist Antonio Cova, a professor at Andres Bello Catholic University in Caracas, said many of Chavez's supporters were experiencing "a state of religious exaltation" because the government has effectively promoted a sort of "religious cult" around the president.

Axel Capriles, a psychoanalyst, said government authorities are seeking to turn Chavez into "a spiritual force" in order to harness his cult of personality.

If officials had provided precise details of the president's condition, Capriles said, they would have made him out to be "a common, ordinary mortal." Instead, he said, they are attempting to portray him as "a person who has superior power, who has magical characteristics."

Some Venezuelans have speculated that the president might be preparing to step down due to his illness and make way for a new election. But even the man Chavez has designated as his successor has shied away from that idea.

"There is only one commander in chief here," Maduro said Saturday on Television. "There is only one president."