The Twitter accounts of Venezuela's acting president Nicolas Maduro (pix) and the ruling socialist party were hacked Sunday as the country went to the polls to pick a new president, officials said.

Maduro campaign chief Jorge Rodriguez said the accounts @NicolasMaduro, @PartidoPSUV and @tmaniglia -- all belonging to the president's office's press secretary -- were hacked.

Then messages appeared including "Electoral Fraud by @lulzsecperu and "HACKED BY @LUZLSECPERU," moments before polls closed in the election for a successor to Hugo Chavez who died of cancer last month, he said.

"This is yet another sign of the enormous desperation" of opposition supporters and their candidate rival candidate Henrique Capriles, Rodriguez said on official VTV television, despite the aparent claim by hacker group LulzSec.

Rodriguez said the hacking was done by the perpetrators of a "dirty campaign from Bogota... which has sought to muddy the electoral process."

Earlier, Maduro himself said a "dirty war" was being fought from Colombia to try to derail Sunday's electoral process.

Maduro specifically accused Venezuelan political adviser Juan Jose Rendon, who works with the Capriles campaign, of being behind what Maduro called a "dirty war to poison the electoral process and sow hatred in the country."