Venezuelan opposition leader Henrique Capriles has held a massive rally in the capital Caracas ahead of next week's presidential election.

An estimated 100,000 people turned up for the gathering against President Hugo Chavez, who faces Capriles in the election.

Launching a tirade against Chavez, Capriles, 40, demanded a thorough probe into the death of three opposition activists during a recent rally.

The activists were killed by gunmen under doubtful circumstances, although the government has already promised an investigation into the killings.

"On Oct 7 [election day] we're going to defeat violence in Venezuela. Our country is tired of the violence, of the division, of the confrontation. ... The time of hatred is going to be buried in Venezuela," Capriles told the cheering crowd.

He asked his supporters to refrain from violence during his last major rally before the election and said: "I ask all Venezuelans, it's not with violence that we're going to face each other. It's vote against vote."

Meanwhile, Chavez addressed a huge gathering in Venezuela's Zulia state, where he vowed to return to power.

"Efficiency, that is one of my promises for the next period. We have to correct things," said the 58-year-old president.

Chavez continued his portrayal of Capriles as a heartless capitalist and pledged the return of socialism.

However in some of his recent campaigns, Chavez has conceded the problems faced by ordinary Venezuelans.

"There are reasons for many people to be dissatisfied with this government that I lead. On Oct 7, it isn't at stake whether the light went out or not... whether they've given me a house or not. Those are very important problems and we're working to solve them. My socialist government is going to continue solving our big problems," said Chavez.

Analysts are predicting a close call which they fear could trigger violence.