Haitians have been shaken by an attack at a campaign rally that killed seven people, but officials say the violence will not derail attempts to hold the nation's first free presidential election campaign.

"The three key elements in the process - the Electoral Council, the army and the people - are determined to go ahead and make a success of these elections," said Ismael Diallo of Burkina Faso, spokesman for the U.N. Election Verification Mission. The sentiment has been echoed by the candidates and election officials.More than 400 international observers, including former President Jimmy Carter, have agreed to monitor the balloting on Dec. 16.

Nevertheless, Wednesday's attack, in which assailants in a jeep hurled a grenade and sprayed bullets on thousands of leftist supporters of the Rev. Jean-Bertrand Aristide, has causd outrage and heightened fears of further election violence.

In addition to the seven killed, more than 50 were wounded, including a 14-year-old girl who had her legs and a hand amputated.

Haiti's last attempt to hold free and fair elections, on Nov. 29, 1987, dissolved in a bloodbath. Thugs shot and hacked to death at least 34 people at polling stations and in the streets. Elections in January 1988 were controlled by the army.

The latest military ruler, Lt. Gen. Prosper Avril, fled into exile in March after widespread demonstrations.