The Labor Department is worried that people could leak its market-moving monthly jobs report to traders before its public release and is reviewing ways to tighten security.
Spokesman Carl Fillichio said Thursday that the department commissioned a study last year by Sandia National Laboratories, a government organization that safeguards the nation's nuclear weapons stockpile.
Sandia was asked to examine the media's access to the reports.
The government arranges so-called "lock-ups" to give reporters 30 to 60 minutes to review the data and prepare stories before they are released to the general public.
The lock-ups are held at the Labor Department and are supposed to be secure. Reporters turn over their cell phones to Labor staff, have no Internet access and are not allowed to leave the room.
Fillichio said the review wasn't sparked by any specific instance of a data leak. The review was reported earlier Thursday by CNBC.
CNBC also reported that the Energy Information Administration, an independent statistical arm of the Energy Department, has blocked computers linked to some Internet addresses from access to its website. Some computers appear to have intentionally slowed the release of EIA data to the public while accelerating it for themselves, the report said.
EIA spokesman Jonathan Cogan on Thursday confirmed the blocking, saying the agency "has taken responsible and appropriate measures to protect the integrity of its data releases."
The EIA's policy prohibits any automated data retrieval program, or robot, that "excessively accesses" information from the website. The EIA will block robots that gain access to the website in any way it considers "excessive or malicious, including robots that attempt to access or download survey information multiple times per second with resulting degradation of service to others," the policy says.
The Labor Department's Fillichio said that for more than 20 years, the lock-ups "have facilitated the news media's ability to carefully review economic data, and provide information and analysis to the public."
He said Sandia was asked to recommend, in light of new technologies, what steps could be taken "to maintain the integrity" of the lock-up process.
"Protecting the integrity and confidentiality of economic data is and always has been a top priority for the Department of Labor," Fillichio said. "We constantly take steps to safeguard sensitive information."
Sandia spokeswoman Heather Clark in Albuquerque, N.M., confirmed that it had done the review but declined to provide details.
The jobs report can move the market strongly in a blink. If traders had advance notice of what the government numbers were going to be, they would have an unfair advantage that could net them millions of dollars in profit.
Last month's report showed the economy added 243,000 net jobs in January, and the unemployment rate fell to 8.3 percent _ the lowest level in three years. That triggered a spasm of buying on Wall Street. The Dow Jones industrial average rose to its highest close since May 2008 _ four months before the financial crisis struck.
The monthly report also has political implications: it reverberates through the presidential campaign and has a potential impact on President Barack Obama's re-election prospects.
The government will release the February report at 8:30 a.m. Eastern time on Friday.
Associated Press writer Sam Hananel contributed to this report.