The U.S. prison population rose 2.8 percent in the 12-month period ending on June 30, 2006, ensuring that the United States continues to have more people in prison than any nation on Earth, Reuters reported June 27.

The U.S. Department of Justice reported that prisons added more than 62,000 new inmates, for a total of roughly 2.245 million people behind bars. The increase was the largest reported in the last six years.

Record numbers of drug offenders, as well as strict sentencing laws and high crime rates, were factors in the increase, experts said. The Bureau of Justice Statistics said that the state prison population rose 3 percent, while jail populations rose 2.5 percent. In federal prisons, the population rose 3.6 percent.