Some of the thousands of trailers sitting unused since they were purchased by the Federal Emergency Management Agency in 2005 for Gulf Coast hurricane victims may finally be put to use — to help victims of last week's tornadoes, officials said Tuesday.

Some members of Congress have accused FEMA of playing down the danger of possible formaldehyde contamination in the trailers — more than 6,300 of them stored at the Hope airport — but an agency spokesman said Tuesday that the trailers are safe.

The decision to use some of the trailers for Arkansas and Tennessee twister victims comes after requests by state officials and members of Arkansas' congressional delegation, who have criticized the trailers in the past as a sign of federal ineptitude after hurricanes Katrina and Rita.

David Maxwell, head of the Arkansas Department of Emergency Management, said his office told FEMA immediately after the tornadoes that the victims would need some of the trailers.

FEMA Administrator R. David Paulison said Friday on a tour of the damage that the agency would prefer putting storm victims in rental property, although he acknowledged that could be difficult in rural areas.

"Knowing rural Arkansas and the areas that were hit, there's not a lot of rental property," Maxwell said. "Then you're stuck with mobile homes."

Maxwell said the number of trailers released would depend on the number of people who called FEMA and requested help, as opposed to simply releasing a blanket number. FEMA already hired a contractor to prepare and possibly move the trailers to people in need, he said.

Tennessee state officials estimate the tornadoes destroyed 517 homes and 61 mobile homes, and estimates in Arkansas suggest about 300 homes were destroyed, likely including a number of manufactured or mobile homes.

FEMA still hasn't reached a firm number of how many mobile homes will be used from Hope and other storage sites around the country, spokesman James McIntyre said Tuesday. The majority of mobile homes stored at Hope were unused and in good shape, with a small percentage refurbished after being used in hurricane relief operations, he said.

Arkansas and Tennessee will receive FEMA mobile homes first because they already were declared federal disaster areas, McIntyre said. Requests from Alabama and Kentucky are still pending, he said.

Phil Parr, who is leading the federal response to the storms in Arkansas, refused to offer any estimates on how many mobile homes would be used or when they would be installed. That would affect "the mind-set of people" seeking aid, he said.

"We're moving as quickly as we've ever moved before," Parr said.

About 250 federal employees will staff an administrative headquarters in Little Rock now open for business in an old factory, Parr said. On Tuesday, workers still stood on ladders looking into ceiling wires, and telephone switchboards stood open.

After Katrina hit in 2005, FEMA purchased 25,000 manufactured homes built at a cost of more than $850 million. Many of them went unused while many hurricane victims remained homeless. All together, FEMA has about 75,000 trailers and mobile home in various locations across the country.

Congress ordered FEMA to stop selling or donating the houses last year after discovering problems with formaldehyde, but McIntyre said FEMA determined its mobile homes in storage at Hope were safe to use.

The mobile homes are about 80 feet long and have two or three bedrooms, McIntyre said.

Tornadoes killed 13 people in Arkansas on Feb. 5, with 12 along the path of just one twister. In all, 56 people died in four states.