WASHINGTON — Online rumors about a big government munitions purchase are true, sort of.

The Homeland Security Department wants to buy more than 1.6 billion rounds of ammunition in the next four or five years. It says it needs them – roughly the equivalent of five bullets for every person in the United States – for law enforcement agents in training and on duty.

Published federal notices about the ammo buy have agitated conspiracy theorists since the fall. That's when conservative radio host Alex Jones spoke of an "arms race against the American people" and said the government was "gearing up for total collapse, they're gearing up for huge wars."

The government's explanation is much less sinister.

Federal solicitations to buy the bullets are known as "strategic sourcing contracts," which help the government get a low price for a big purchase, says Peggy Dixon, spokeswoman for the Federal Law Enforcement Training Center in Glynco, Ga . The training center and others like it run by the Homeland Security Department use as many as 15 million rounds every year, mostly on shooting ranges and in training exercises.

Dixon said one of the contracts would allow Homeland Security to buy up to 750 million rounds of ammunition over the next five years for its training facilities. The rounds are used for basic and advanced law enforcement training for federal law enforcement agencies under the department's umbrella. The facilities also offer firearms training to tens of thousands of federal law enforcement officers. More than 90 federal agencies and 70,000 agents and officers used the department's training center last year.

The rest of the 1.6 billion rounds of ammunition would be purchased by Immigration and Customs Enforcement, the federal government's second largest criminal investigative agency.

ICE's ammunition requests in the last year included:

_450 million rounds of .40-caliber duty ammunition

_40 million rounds of rifle ammunition a year for as many as five years, for a total bullet-buy of 200 million rounds

_176,000 rifle rounds on a separate contract

_25,000 blank rounds

The Homeland Security ammo buy is not the first time the government's bullets purchases have sparked concerns on the Internet. The same thing happened last year when the Social Security Administration posted a notice that it was buying 174,000 hollow point bullets.

Jonathan L. Lasher, the agency's assistant inspector general for external relations, said those bullets were for the Social Security inspector general's office, which has about 295 agents who investigate Social Security fraud and other crimes.

Jones the talk-show host did not immediately respond to requests for comment.