PINAR DEL RIO, Cuba – Packing ferocious winds and whipping up monstrous waves, Hurricane Ivan’s eye brushed Cuba’s sparsely populated western tip as a treacherous Category 5 storm – the most powerful – and barreled north toward the American Gulf Coast.

Ivan, one of the strongest storms on record, hammered Grand Cayman with wind gusts up to 200 mph before reaching Cuba. The storm has killed at least 68 people across the Caribbean and threatens millions more in America.

The wall of Ivan’s eye clipped the tip of Cuba at about 6:45 p.m. as it moved through the Yucatan Channel on its way to the Gulf of Mexico, the island’s top meteorologist reported.

The slow-moving storm, carrying 160-mph winds, has American residents from the Florida Panhandle to Louisiana preparing to flee the Gulf Coast.

The hurricane hit hours after President Castro stopped to discuss preparations in Pinar del Rio city, where residents shouted “Fidel! Fidel!”

Mr. Castro said he would not accept any hurricane aid from America. “We won’t accept a penny from them,” the Cuban leader said.

“The hurricane before this, they offered $50,000, an insignificant amount,” he said referring to aid the American government offered after Hurricane Charley. “Even if they offered all that was necessary – $100 million, $200 million, we would not accept. We can recuperate on our own.”

As the hurricane’s western edge drenched fields in Cuba’s Pinar del Rio province, 20-foot-tall waves still were slamming the sea wall at the port in George Town, Grand Cayman, the wealthy British territory that is a popular scuba diving destination and offshore banking center.

The Associated Press flew over the Cayman Islands yesterday, surveying Grand Cayman, where houses had been reduced to piles of plywood. A hangar at the airport in George Town had its roof blown off. Officials said the airport was not functioning and planes were being turned away.

The only signs of activity on the ground were animals congregating on higher ground. In Cuba – despite Mr. Castro’s bravado – residents said they feared for their lives.

“The wind blew like it was the end of the world,” said Odalys Lorenzo, a community official at a shelter in southwest Cuba. With Hurricane Charley, people thought they would lose all their possessions, but “with this one, they were afraid of losing their lives,” he said.

As Ivan moved in, Cuban state TV reported waves up to 15 feet crashing onto the southern coast of the Isla de Juventud southwest of the main island. Ivan swirled toward cropland that produces Cuba’s famed cigars, a region still recovering from the effects last month of Hurricane Charley. About 1.3 million Cubans were evacuated from particularly vulnerable areas.

The tobacco crop – the country’s third-largest export – was safe, according to top grower Alejandro Robaina. Planting doesn’t begin until next month, and what remains of the January harvest is protected in curing houses.