This is IN THE NEWS in VOA Special English.

Crime ratesin the United States have been dropping for a number of years. Rates of violent crime have fallen to their lowest levels since the 1970s. President Bush noted this in his declaration in April for National Crime Victims' Rights Week.

But this week, a report from the Federal Bureau of Investigation offered new evidence that violent crime may be on the rise. Early numbers for the first half of the year show violent crime was up three and seven-tenths percent over the same period last year.

The F.B.I. reported earlier that violent crime increased more than two percent in all of 2005. That was the largest increase in fifteen years.

The new report says the number of robberies nationwide increased nine and seven-tenths percent between January and June of this year. And there were seven percent more arson fires compared to the first half of last year.

The number of murders increased almost one and one-half percent. Other violent offenses were also up more than one percent. But the F.B.I. says the number of rapes decreased, though by less than one-tenth of one percent.

The report shows that violent crime rose nationwide, especially in cities with populations between half a million and a million. But the largest increase was in the West. Violent crime in that part of the country rose almost five percent. Northeastern states had the smallest increase. It was three percent over the same period last year.

While violent crime increased nationally, most property crimes fell in the first half of the year. In all, property crime decreased more than two and one-half percent

The information in the F.B.I. report comes from more than 11,000 law enforcement agencies.

Researchers from the Justice Department are studying a number of cities to look for reasons why violent crime is up nationally.

Experts suggest a number of possible reasons. These include too many illegal guns and not enough law enforcement officers on the streets of American cities.

Also blamed are reductions in federal money for local law enforcement agencies over the past ten years. Yet local agencies have more duties since the attacks of September eleventh, 2001. Now they are expected to fight terrorism in addition to traditional crime.

At the federal level, the F.B.I. and other agencies that often help local officers investigate crimes have seen their duties change as well.

But other researchers believe an increase in young males and other population changes have played a part in the rise in violent crime. And some point to increases in the spread of street gangs.

In any case, the F.B.I. notes that in the years leading up to 2005, violent crime kept falling. So officials say it is still too early to say if new trends are developing.

IN THE NEWS in VOA Special English was written by Brianna Blake. I'm Steve Ember.

crime rate : 犯罪率