Hurricane-force winds tore roofs off buildings, uprooted trees and pushed towering surf inland, flooding entire neighborhoods across Alabama's Gulf Coast as the Texas-sized storm raged through the night.

After making landfall at 2:00 am (0600 GMT) between Mobile, Alabama and Pensacola, Florida with winds of 215 kilometers (135 miles) per hour, Ivan gradually began to decrease in strength.

The National Hurricane Center downgraded Ivan to a tropical storm with maximum sustained winds of 97 kph (60 mph).

Authorities confirmed 11 deaths, including six in Florida, two in Mississippi, two in Louisiana and one in Georgia. Local media reported three more deaths in Florida.

Hundreds of thousands of people were without power in Alabama and the streets of Mobile were littered with fallen trees, smashed traffic lights and other debris.

Around the resort town of Gulf Shores, dozens of people were trapped by flood waters, which in some areas reached as deep as three meters (nine feet).

Florida has been receiving federal aid since two earlier hurricanes, Charley and Frances, hit the state over the past six weeks.

President George W. Bush declared Alabama, Mississippi and Louisiana disaster areas as well, so they could also quickly receive federal aid.

Bush will skip weekend campaign events in favor of traveling to Alabama and Florida to observe disaster relief efforts, the White House said.

Authorities imposed curfews in the worst-hit areas along the Gulf of Mexico coast to prevent looting and help emergency teams get around the affected zones.

Some 2,000 Florida National Guard soldiers were headed toward northwestern Florida, the Pensacola News Journal daily reported on its website.

"Again, like Frances and Charley, we're not waiting for confirmation on how bad it is," state Emergency Management Director Craig Fugate told the Florida daily.

"I'm starting to take these hurricanes personal," he said.

Ivan was weakening over central Alabama, 40 kilometers (25 miles) south-southwest of Birmingham, Alabama, the hurricane center reported at 2100

The center said Ivan could spawn more tornadoes in parts of Alabama, Tennessee, South Carolina, North Carolina and Georgia.

Ivan, one of the 16 most-powerful storms to hit the United States since 1900, had already killed more than 70 people as it made its way across the Caribbean before entering the Gulf of Mexico.

At least six people were killed by tornadoes in northwestern Florida, while a youth died when a tree crashed into a mobile home and two women were found dead in the rubble of residencies, local media and authorities said.

In Louisiana, two women died while being transferred from residences for the elderly to shelters, an emergency services spokeswoman said.

Authorities in Mississippi said a man died of electrocution while fixing a television antenna, while a second man was hit by a falling tree branch.

A tree fell on a car in Georgia, killing its driver, officials said.

Ivan's winds and torrential rains were the main concern along the US Gulf Coast, where hundreds of thousands of people evacuated their homes before it arrived.

Before heading into the Gulf of Mexico, Ivan rampaged across the Caribbean, from Grenada to Cuba.

Grenada was the worst hit by Ivan, with at least 37 people killed last week and up to 90 percent of all buildings damaged or destroyed, officials said.

In Jamaica, police put the death toll at 21 after the powerful winds from Ivan tore down houses, felled trees and destroyed roads in the nation of 2.7 million.

Meanwhile, Puerto Rico reported two deaths when another storm, Jeanne, barreled into the island Wednesday, while a Pacific hurricane, Javier, was moving along the Mexican coast.

Jeanne, which was downgraded to a tropical storm, could regain hurricane strength, the hurricane center warned. It was located 100 kilometersmiles) northeast of Santo Domingo at 0001 GMT.

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