WASHINGTON, Oct.23 (Xinhuanet) -- The United States has the world's largest prison population and the figure is still growing, a government report said Sunday.

    According to a report released by the Bureau of Justice Statistics of US Justice Department, the US prison population, already the largest in the world, grew 1.9 percent to 2,267,787 people last year.

    However, the growth rate was lower than the average 3.2 percentin the last decade.

    The report said the US incarceration rate, also highest among all countries, hit 486 sentenced inmates per 100,000 last year, up 18 percent from 411 a decade ago.

    The five states with the highest incarceration rates in 2004 were all from the South, led by Louisiana with 816 sentenced prisoners per 100,000 residents.

    Meanwhile, the five states with the lowest rates were all from the North, with Maine experiencing 148 sentenced inmates per 100,000 residents.

    Paige Harrison, coauthor of the report, attributed some of the prison population rise to tougher sentencing policies implemented in the late 1990s.

    She said the average time served by prisoners today is seven months longer than it was in 1995.

    "You bring more people in, you keep them longer......inevitablyyou're going to have growth," she said.

    The Justice Policy Institute, a legal thinktank, said the statistics show little relationship between prison population growth and the crime rate, which has been falling in recent years.

    An earlier government report said the US violent crimes during 2004 were at the lowest level in over three decades.

    Given the ever-expanding prison population, US legal experts urged policy-makers to reconsider current sentencing policies, in order to avoid expensive incarceration costs and to invest in moreproductive prevention and treatment approaches to crime. Enditem