The rate was 6.8 people killed per 100,000 - equivalent to 18,209 murders - the lowest level since 1967 when the level was 6.2 per 100,000. In 1950 the rate was 4.6 per 100,000.

Much of the decline came in larger cities - those with a population of more than one million people - where the murder rate fell from 35.5 per 100,000 in 1991 to 20.3 per 100,000 in 1997.

Further decline expected

Chicago's urban poverty is thought ot be one reason for its high rate

The Clinton administration says the figures showed American cities were "the safest they had been in a generation", and that the sharp drop was due to new anti-crime laws.

"A variety of studies show that crime, and especially homicide, should continue to decline into the next year, and that is good news for Americans in 1999," a White House statement said.

The murder rate increased sharply in the 1980s, but has been in steady decline for several years. Violent crime in general has also fallen to its lowest level for many years.

Racial divide

The report also found that from 1976 to 1997, 85% of white murder victims were killed by whites and 94% of black victims were killed by blacks.

During the same period, blacks were seven times more likely than whites to be homicide victims and eight times more likely than whites to commit homicides.

In other figures released, Chicago became the murder capital of the US in 1998, with 698 homicides -surpassing New York City's total for the first time, which itself has seen a dramatic drop in killings.