The nation's murder rate rose slightly last year but the number of robberies skyrocketed by 6 percent, preliminary FBI data released Monday show.

The statistics were part of an overall 1.3 percent rise in violent crime across the country in 2006 -- the second straight annual increase.

However, car thefts, arsons and other property crimes dipped for the second straight year, the data show.

The modest increase in murders reflected a mixed bag for cities. The number of homicides in major metropolitan areas -- those with at least 1 million residents -- climbed by 6.7 percent. Smaller cities, meanwhile, saw their murders decrease by a collective 11.9 percent.

The spike in robberies marked the highest increase in any category of crime surveyed in the FBI report, which was compiled with data from more than 11,700 law enforcement agencies nationwide.

Violent crime rose in every region of the country except for the Northeast, the FBI reported. Western states saw the largest jump in violent crime, by 2.8 percent, the data show.

The new numbers come amid a Justice Department push to tamp down violent crime with millions of new dollars in funds to local police and a surge of federal agents to troubled cities. Attorney General Alberto Gonzales -- who took office as violent crime started to rise -- has called the crackdown one of his top priorities for the remaining 18 months of his tenure at the Justice Department.

In a spot of good news, violent crime grew at a slower pace than initially expected. In December, the FBI projected a 3.7 percent increase for the first six months of 2006. The year before, in 2005, violent crime rose by 2.3 percent.

Property crimes decreased overall by 2.9 percent from 2005, the FBI reported. Burglaries, however, rose slightly -- particularly in mid-sized cities, where the rate grew by 3.3 percent.