SAN JUAN, Puerto Rico (AP) _ Beleaguered residents of Puerto Rico and the Virgin Islands scrambled to prepare for Hurricane Lenny, a late-season surprise that gathered strength over the normally placid Caribbean and headed for the U.S. territories today.

Lenny's sustained winds strengthened to nearly 135 mph today, a Category 4 hurricane capable of extreme damage. At 8 a.m. EST, its center was located about 70 miles southwest of St. Croix and it was headed east-northeast at 13 mph on a path that could make a direct hit on the Virgin Islands.

In Puerto Rico, Gov. Pedro Rossello said today that 4,725 people had sought refuge in 191 shelters set up by the government. About 100,000 people were without water, and 90,000 were without electricity. One man died when he fell while trying to board up his windows.

In St. Croix in the U.S. Virgin Islands, callers to radio stations reported flooding in many areas and a few beached boats in the town of Frederiksted, and some roofs torn from homes. About 130 people took shelter in a high school, officials said.

Lenny passed south of heavily populated and vulnerable Haiti and the Dominican Republic on Tuesday, staying on its unusual west-to-east course. It then veered northeast, sparking a last-minute rush at grocery stores and gas stations throughout the islands in its path.

Officials in Puerto Rico and the U.S. Virgin Islands warned that the storm could dump up to 15 inches of rain. The National Weather Service warned of isolated tornadoes.

At a Home Depot near San Juan, nervous shoppers Tuesday night consulted a large wooden map where employees posted stickers tracking Lenny's relentless advance.

``We're taking no chances,'' said Gadiel Rivera, a 30-year-old accountant buying plywood to board up the windows of his home. ``Everyone remembers Georges, who gave Puerto Rico a real beating.''

Hurricane Georges, which hit in September 1998, steamrolled the island and killed more than 500 people throughout the Caribbean.

The combination of the late date and easterly path left even experienced observers agape. ``It's unheard of,'' said veteran meteorologist John Tewey on San Juan's WOSO-AM radio. ``This is a once-in-a-lifetime event.''

There were growing concerns about a group of protesters camping out on a U.S. Navy bombing range on Puerto Rico's outlying island of Vieques. The protesters, who are opposed to live-fire training on the island, planned to ride out the storm inside an abandoned army tank used for target practice by the military.

Hurricane warnings remained in effect for Puerto Rico, the Virgin Islands, St. Martin, Anguilla, St. Kitts and Nevis, Montserrat and Antigua and Barbuda.

Farther east, the storm hurt the endeavors of a Kentucky lawyer attempting to become the first American and the first woman to row solo across the Atlantic. Tori Murden has rowed more than 2,500 miles since she left the Canary Islands in mid-September and is within 400 miles of her destination, the French islands of Guadeloupe. But waves stirred up by the storm have been pushing her back.

In the U.S. Virgin Islands, Gov. Charles Turnbull declared a state of emergency and a curfew after 9 p.m. to prevent looting, and the U.S. National Guard was placed on alert. Tourists crowded at airline ticket counters in an increasingly vain effort to leave. The St. Croix airport closed, and the St. Thomas airport was scheduled to close.

In the nearby British Virgin Islands, schools, government offices and airports closed Tuesday afternoon. Only nurses, doctors, police and essential workers remained.

Cruise ships docked in San Juan and in St. Thomas headed out to sea to escape the storm, and airlines canceled flights to and from both places.