Hurricane Gustav dumped torrential rains across southern Haiti on Tuesday, killing at least one man and threatening crops amid protests over high food prices. Global fuel futures soared on fears Gustav could move into the Gulf of Mexico as an "extremely dangerous" storm.

Track Gustav | Hurricane Guide

Trees toppled as the storm lingered for hours over Haiti's poor, deforested southern peninsula, and water levels were rising in banana, bean and vegetable fields. One man was killed in a landslide in the mountain town of Benet, civil protection director Marie Alta Jean-Baptiste told Radio Metropole.

Hundreds of people in coastal Les Cayes ignored government warnings to seek shelter, instead throwing rocks to protest the high cost of living in the Western Hemisphere's poorest country. Witnesses said U.N. peacekeepers used tear gas to disperse the crowd.

Oil prices shot up $5 a barrel Tuesday after the National Hurricane Center predicted Gustav could enter the gulf as a major hurricane this weekend. Prices of futures in natural gas, heating oil and gasoline also rose.

If Gustav continues on its path, it could drive up U.S. gasoline prices by 10 cents a gallon ahead of Labor Day weekend, predicted James Cordier, president of Tampa, Florida-based Liberty Trading Group and OptionSellers.com.

Forecasters said Gustav should slice along the southern coast of Cuba all week and grow into a perilous Category 3 hurricane with 120 mph (190 kph) winds before entering the central gulf on Sunday. Forecasters were reluctant to predict the storm's path beyond the weekend, the third anniversary of Hurricane Katrina.