Democratic vice presidential nominee Joe Biden received five student draft deferments during the Vietnam War, the same number of deferments received by Vice President Dick Cheney, and later was disqualified from service because of asthma as a teenager.

Officials with Democratic presidential nominee Barack Obama's campaign released Biden's Selective Service records at the request of The Associated Press. Less detailed records were available from a National Archives facility in Philadelphia.

According to the documents, Biden, 65, received several deferments while he was an undergraduate at the University of Delaware and later as a law student at Syracuse University. A month after undergoing a physical exam in April 1968, Biden received a Selective Service classification of 1-Y, meaning he was available for service only in the event of national emergency.

"As a result of a physical exam on April 5, 1968, Joe Biden was classified 1-Y and disqualified from service because of asthma as a teenager," said David Wade, a campaign spokesman.

In "Promises to Keep," a memoir that was published last year and became an instant best-seller after he was tapped as Obama's running mate, Biden never mentions his asthma, recounting an active childhood, work as a lifeguard and football exploits in high school.

The Obama campaign pointed to media interviews from 1987, when Biden was making his first bid for the presidency, that mention his asthma.

Military service and questions about which presidential ticket would be stronger on national security are intertwined in the presidential race. Republican John McCain, a former Navy pilot who spent 5 1/2 years in a Vietnamese prison, has argued that he has stronger background to be commander in chief. Democratic nominee Barack Obama counters that McCain would continue a wrong-headed foreign policy from the Bush administration.

Biden has had extensive experience with national security issues in the Senate. McCain's running mate, Sarah Palin, has been Alaska governor for two years and before that was a small-town mayor.

Biden's five student deferments equal the number given to Vice President Dick Cheney, who has been quoted as saying he had "other priorities" than military service in the 1960s.

According to records AP obtained from the National Archives, Biden registered Feb. 15, 1961, with the Selective Service, when he was an 18-year-old student at Archmere Academy in Wilmington. The archives documents do not include any information about his classification or physical exam.

Documents provided by the Obama campaign indicate Biden received a classification questionnaire in October 1963, when he was enrolled at the University of Delaware, and received his first 2-S student deferment a month later. Additional deferments were granted in roughly 12-month intervals, the last coming in January 1968, shortly before he graduated from law school at Syracuse University.

Then in April 1968, when he was 25, Biden was disqualified from service due to asthma.