The number of people killed on U.S. highways rose in 2012 to enda run of six consecutive declines, which was the longest streak inthe nation's history.

Crash fatalities rose 5.3 percent to an estimated 34,080 from ayear earlier, the U.S. National Highway Traffic SafetyAdministration (NHTSA) said today in a report. The jumpcoincided with Transportation Secretary Ray LaHood's campaignagainst distracted driving.

The fatality rate, or the number of people killed for every 100million vehicle miles traveled (VMT), rose also, from 1.1 in 2011to 1.16 in 2012. The estimated fatality rates per 100 million VMTduring the first, second, and third quarters of 2012 were 1.09,1.13, 1.22 and 1.19, respectively.

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Although the NHTSA previously pointed to declines in death rates as evidence of success in promoting safety evenwhen absolute numbers rose, it offered no explanation for lastyear's increase. The agency did, however, note the preliminarynature of these numbers and that final figures will be releasedlater this year.

One possible factor in the overall uptick is the increase inmotorcycle deaths. In a report issued last month, the GovernorsHighway Safety Association said that motorcyclist deaths increasedabout 9 percent last year to more than 5,000.

The Federal Highway Administration says the increase infatalities outpaced a 0.3-percent rise in the number of milesdriven in the U.S. The number of people killed in 2012 on U.S.roads was the highest since 2008, which was the third of sixconsecutive years of declines.