Venezuelan President Hugo Chavez has returned home after 11 days of cancer treatment in Cuba, saying his latest round of radiation therapy was successful.

"I should say that we have successfully completed the medical treatment," the socialist leader said as dozens of uniformed soldiers holding assault rifles stood in formation along a red carpet on the tarmac at Simon Bolivar International Airport.

"Of course, I must rigorously follow the medical advice in these coming days in order to continue recuperating," he said.

"Aside from some discomforts that are normal in this type of treatment, absolutely nothing occurred that forced it to be stopped, suspended or make changes to the initial plan," added Chavez, disclaiming rumours that complications arose during his treatment.

State television broadcast live footage of Chavez greeting and chatting with Vice-President Elias Jaua, Defence Minister Henry Rangel Silva and Justice Minister Tareck El Aissami and other aides after he stepped off the plane.

Chavez, 57, travelled to Cuba on April 30 for further radiation therapy.

In good spirits

The socialist leader looked energetic and seemed to be in good spirits, breaking out in song before finishing his nationally televised address.

He began the treatments in late March after an operation in February that he says removed a second tumour from his pelvic region. The first tumour was taken out in an operation last June.

Chavez has kept some details of his illness a secret, including the type of cancer and the precise location of the tumours.

Crossword conspiracy

A state TV host's allegation that a newspaper crossword puzzle may have had a hidden call for a plot to kill President Hugo Chavez's elder brother has drawn ridicule from government critics and even some supporters.

Miguel Perez Pirela pointed out that Wednesday's crossword contained the word "asesinen" (kill), intersecting with the name of Chavez's brother, "Adan." He noted they were below the word "rafagas," meaning either gusts of wind or bursts of gunfire.

Neptali Segovia, an English teacher who has prepared crossword puzzles for the newspaper Ultimas Noticias for 17 years, denied the accusation, turned himself in to police and was released after questioning.

Nestor Francia, a poet and writer who favours Chavez's socialist government, said the report "doesn't at all lend weight to our credibility in terms of the right's conspiratorial plans. From what cheap spy movie does someone get that orders for killings be given through a crossword?"

The president's treatment has forced him to slow his daily routine and prevented him from actively campaigning as he has in the past. Opposition presidential candidate Henrique Capriles has been travelling across this South American country for weeks to drum up support ahead of an Oct. 7 presidential election.

Chavez vowed to reinvigorate his campaign.

"As the hours and days pass, I'm sure that with God's favour, medical science and this soldier's body that envelops me, I will get back to where I must be, in the front line of the battle, alongside the Venezuelan people, promoting the socialist revolution."

Upon his return, Chavez accused his political adversaries of leading an international campaign aimed at raising doubts regarding his commitment to democracy. He also claimed opposition groups are planning to stir up violent political upheaval ahead of the upcoming vote. He did not provide details or single out any particular organization.

The president was echoing accusations against government foes that his allies have made recently.

Capriles told journalists earlier Friday that he opposes any type of violence.

"I'm against any type of violence, no matter where it comes from," said Capriles, speaking during a campaign event in the president's home state of Barinas.

Thanks Castros

During his stay in Havana, Chavez discussed means of accelerating Venezuela's drive toward socialism with Fidel Castro, one of his political mentors.

"The transition to socialism requires increased social justice and equality every day," he said. "Yesterday, I was speaking with my colleague and comrade Fidel about these issues."

Chavez thanked Cuban President Raul Castro and his elder brother for providing medical care as he attempts to overcome his illness.

"I want to thank Fidel, Raul and all of Cuba: Their solidarity, attention, generation," he said, prompting applause from a small crowd present at the airport.

Under Chavez, Venezuela and Cuba have become close allies while relations between Caracas and Washington have soured.