Kabul, Afghanistan - Afghan authorities say a roadside bomb killed eight civilians in southern Afghanistan when it struck their vehicle.

The governor's office in Helmand province says the Wednesday afternoon explosion in Marjah district was massive and that the bodies are difficult to identify.

The U.N. says last year was the deadliest on record for civilians in the Afghan war, with 3,021 killed as insurgents ratcheted up violence with suicide attacks and roadside bombs.

The U.N. says Taliban-affiliated militants were responsible for more than three-quarters of the civilian deaths in 2011.

Source: The Associated Press