By Andrew Cawthorne and Daniel Wallis
CARACAS (Reuters) - Venezuela's opposition leader Henrique Capriles dismissed as irresponsible on Tuesday a government warning of an assassination plot against him that further stirred up an already volatile election campaign.
President Hugo Chavez made the surprise announcement on Monday evening, implying that elements within the opposition were behind a plan to kill Capriles, the 39-year-old Miranda state governor who is challenging him in an October 7 election.
"The declaration of the Socialist Party candidate borders on the irresponsible, like his government is with the insecurity our people have to live with," Capriles said via Twitter.
The latest development adds to a nervous and polarized atmosphere across the South American OPEC member, which the socialist Chavez has dominated for 13 years.
Shots were fired during one Capriles campaign stop in Caracas earlier this month, and officials from Chavez down have pilloried him as a "pig," "bourgeois" and a "little Yankee."
Foes frequently call Chavez a "dictator."
The president is recovering from cancer surgery and is due to start radiation therapy in the coming days. The treatment is expected to weaken him during the campaign and has triggered rumors in some circles that he has a life-threatening condition.
Nevertheless, Chavez has a healthy poll lead over his rival, thanks, analysts say, to his strong emotional connection with the poor and oil-financed spending on welfare projects.
Chavez kept up his verbal attacks on the opposition in a televised cabinet meeting later on Tuesday. "They have no project, no leadership, nothing ... they are the guarantors of chaos. We're the guarantors of national development," he said.
Robert Serra, a member of parliament from his ruling Socialist Party, told local TV the existence of a plot to kill the opposition leader had not been 100 percent confirmed.
"But this was a most prudent decision by the government, to make public the possibility," Serra said. "We want the campaign to proceed with peace and tranquility."
Capriles, a center-left politician who hails Brazil as his model, said the assassination talk was a distraction from daily problems that trouble Venezuelans, such as a violent crime rate that is among the worst in the world.
"Our people have been living with insecurity, violence, lack of peace for years," Capriles said on Twitter. "My fight is for a country without violence and we will achieve it!"
The governor, who is the candidate of the Democratic Unity coalition that groups the country's main opposition parties, dismissed an offer from Chavez of state protection.
"A president should not 'offer' protection to one Venezuelan - he should guarantee it for all," Capriles said.
Chavez gave few details of the alleged plot in a phone call to state TV late on Monday, but said Venezuela's intelligence chief had met Capriles aides "because there's some information out there that they want to kill him."
Chavez said the plot had not come from government supporters, but rather from among criminal destabilizers linked to the opposition itself.
Venezuelan analyst Diego Moya-Ocampos said the authorities may be worried about how to rein in armed pro-Chavez militants.
"The government might therefore be trying to introduce a strategy to deflect potential criticism, in the event of an attack against Capriles triggered by pro-government armed groups that the government cannot control," he said.
That did not rule out the possibility extreme opposition groups could also generate violence and instability, he added.
Capriles' combative response to Chavez marked a change in tone. In the past he has sought to avoid confrontation with the president and to project himself as the man to solve grassroots problems, rather than engage in rhetorical battles.
In a speech later on Tuesday, he said he did not know whether to take Chavez's words as a warning - or as a threat.
This month, the opposition leader began a nationwide "house-by-house" tour in a simple bus and with notably little security.
Wearing T-shirts and often splattered with mud, Capriles has plunged in and out of homes and shops, and walked the streets for hours to talk to voters and hear their problems.
Chavez supporters say Capriles has copied the style of their man, who ran an on-the-street campaign in 1998 to sweep to a first presidential victory and embark on the "revolution" that has made him one of the world's most recognizable leaders.
(Editing by Lisa Shumaker)