After falling for three years in a row, the number of automobile fatalities in New Jersey rose in 2011, according to preliminary data from the State Police.

A total of 627 people died in 586 accidents on the state's roads last year, the data shows. That represented an 11 percent increase in the number of fatal accidents and a 12.8 percent rise in the number of deaths over 2010, when numbers hit a 30-year low. It was the first increase since 2006, when there were 708 accidents resulting in 770 deaths. Still, the number of fatalities is roughly half of the high of 1,160 in 1981.

The uptick may have been an aberration. State officials say the number of traffic fatalities during the first half of this year is 10 percent lower than at the same time last year, 262 through June of 2012 compared with 291 in the first half of 2011.

“We are encouraged by the decline in traffic-related fatalities thus far,” said Division of Highway Traffic Safety Acting Director Gary Poedubicky.

State police reports show that, typically, alcohol was involved in 3 of 10 fatal accidents. Driver distractions and speeding are also factors in a significant number of deadly crashes.

By far, most of those killed in accidents are drivers. Last year, 362 or almost 6 of every 10 fatalities were drivers. The second-highest rate of casualties was for pedestrians -- 143 of those killed. Another 105 were vehicle passengers and 17 were cyclists.

More than 50 people died in roadway accidents in Middlesex, Essex, Burlington, and Ocean counties last year. By contrast, Cape May had fewer than 10 traffic fatalities. Hudson County had the highest rate of fatalities compared with its roadway miles -- more than 4 died on every 100 miles of road. Essex was second, with a rate of more than 3 per 100. Those two counties are the most densely populated and second most densely populated in the state. In contrast, Hunterdon, Sussex, Cape May, Morris, and Monmouth all had fewer than one death per 100 miles of road.

However, comparing fatalities to vehicle miles traveled brings a different result. Using that measure put two of the state's least populous counties, Cumberland and Salem, at the top of the list, with more than 7 fatalities per 1 million vehicle miles driven in 2011. By contrast Bergen County, which had the most vehicle miles driven of any county -- 20.4 million -- had the lowest rate, 1.5 deaths per 1 million miles driven.

With 14 fatal accidents, Woodbridge had the highest number of any municipality, followed by Egg Harbor with 12.

To see more information about the fatal accidents in a county, including the number of accidents, counts of who died, roadway and vehicle miles driven, and fatality rates based on those measures, click on a county.

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