Ahmadzia Abdulzai, a spokesman for the governor of Nangarhar province, said the guests were shot dead in their sleep late on June 8 after the wedding party in the Dur Baba district on the border with Pakistan.

The groom, his father and cousins were amongst the dead, district chief Haji Hamesha Gul said, adding that some were also his own relatives.

They were sleeping outside, common amongst Afghans in the hot summer months, when the gunmen opened fire, he added. No one claimed immediate responsibility.

A year ago a suicide bomber killed at least 40 people, a quarter of them children, at a wedding party in Afghanistan's south. Though the Taliban denied responsibility, they have made it clear they oppose music and dancing.

During their austere rule, which was toppled by US-backed Afghan forces in 2001, the Taliban banned television and music as un-Islamic.

Also in the Nangarhar province two years ago, insurgents snatched five Afghan musicians from a wedding party, shaved their heads and tied them to a tree as punishment. The musicians were made to swear they would find other ways to make a living before they were released.

Violence is escalating in Afghanistan in the tenth year of an increasingly unpopular war. Afghan and foreign security forces, as well as government officials, are often targeted in attacks by insurgents.

The Taliban said last month it had begun its long-awaited "spring offensive" and senior US commanders said they expected a significant spike in violence.