The government has recommended a site in Kansas for a new $450 million laboratory to study biological threats such as anthrax and foot-and-mouth disease, officials said Wednesday.

The Homeland Security Department's choice of Manhattan, in central Kansas, beat out intense competition from sites in Georgia, Mississippi, North Carolina and Texas.

Agency officials disclosed their decision to several lawmakers late Tuesday, according to lawmakers and staff familiar with the briefings. The officials spoke only on condition of anonymity because an announcement will not come until later this week.

The choice is not final until sometime after a 30-day period for comments on the decision, which could face legal challenges from losing states.

Homeland Security spokeswoman Amy Kudwa said the department would have no comment until the public announcement.

The new National Bio and Agro-Defense Facility would replace an aging 24-acre research complex on Plum Island, about 1.5 miles off the eastern shore of New York's Long Island. Foot-and-mouth research has been confined to the island since 1955 to avoid an accidental outbreak that could lead to the slaughter of millions of livestock. The disease does not sicken humans.

Some farm groups have expressed concern about the risks of moving the lab to the U.S. mainland. The Bush administration acknowledged this year that accidents have happened with the virus on Plum Island.

But Homeland Security officials are convinced that the new lab can operate safely using the latest containment procedures. Kansas officials are focused on the $3.5 billion economic infusion the lab could mean for the local economy.

A draft copy of Homeland Security's "Preferred Alternative Selection Memorandum," prepared by Undersecretary Jay Cohen and obtained by The Associated Press, concludes that the site on the campus of Kansas State University was chosen based on its proximity to existing biohazard research, strong community acceptance and a generous package of incentives by the state.

"The Steering Committee unanimously agreed that the Manhattan campus site is the preferred alternative and I concur with the Steering Committee's recommendation," Cohen says in the draft document.

Mississippi Gov. Haley Barbour said he was "very seriously" considering whether to challenge the decision.

"We've got a little time to prepare our appeal," Barbour said at a news conference.

The lab is expected to generate about 1,500 construction jobs and a permanent payroll of $25 million to $30 million for more than 300 employees once the project is completed by 2015.

The Kansas Legislature approved $105 million in bonds to buy land, upgrade roads, install a security fence and build a utility plant at the university site. The school already conducts similar research at its Biosecurity Research Institute, near the proposed site of the new lab.

Besides foot-and-mouth disease, researchers also would study African swine fever, Japanese encephalitis, Rift Valley fever and the Hendra and Nipah viruses.

Other finalist sites were Flora, Miss.; Athens, Ga.; Butner, N.C.; and San Antonio.