Boats and debris for hurricane Ike litter I-45 leading onto the island of Galveston, Texas, Sunday, Sept. 14, 2008. (LM Otero/Associated Press)

Rescue crews went door to door Sunday in coastal neighbourhoods of Texas and Louisiana that were inundated by Hurricane Ike's storm surge, racing to check on those who spent a second harrowing night trapped amid flattened houses, strewn debris and downed power lines.

Ike is so far blamed for four deaths — two in Texas and two in Louisiana — where the storm flooded thousands of homes and cut power to about three million people.

Officials don't yet know the full extent of the damage, but it's becoming clear the devastation is extensive.

U.S. President George W. Bush announced Sunday that he'll travel to the hardest-hit areas on Tuesday to lend support to the victims, many of whom remain in their flooded homes.

Authorities said as many as 140,000 people in coastal areas of Texas stayed in their homes when Ike came ashore as a Category 2 storm early Saturday.

A home is surrounded by floodwaters in Galveston, Texas, after Hurricane Ike hit. (David J. Phill/Associated Press)

Waist-deep water and downed trees kept many rescuers from reaching people in Galveston. Paramedic Stanley Hempstead said that as he helped people in the island city, he was reminded of another disastrous storm that kept him working for 31 days.

"This brings back memories of Katrina — a lot of torn-up homes and flooded stuff," he said of the hurricane that struck New Orleans three years ago. On one side of the Galveston Peninsula, a couple of barges had broken loose and smashed into homes.

Everything from red vinyl barstools to clay roof tiles littered the landscape. Some homes were "pancaked," the second floor sitting where the first had been before Ike's surge washed it out. Only the stud frames remained below the roofs of many houses, opening a clear view from front yard to back.

There is also widespread damage in Houston, where officials have announced a 9 p.m. to 6 a.m. weeklong curfew. In the downtown area, winds shattered skyscraper windows, sending glass, furniture and business documents onto the streets below.

Bush said it was too early to determine to extent of the damage the hurricane had on gasoline production and pipelines.

The U.S. Energy Department said on Sunday it would send 309,000 barrels of crude oil from the country's emergency stockpile to two refineries that are running short of supply because of hurricanes Gustav and Ike.

Ike was downgraded to a tropical storm Saturday afternoon. By mid-morning Sunday, it was classified as a tropical depression and was moving over southern Missouri with winds of up to 56 km/h, the U.S. National Hurricane Center said.

With files from the Associated Press