Kandahar, Afghanistan: The Taliban beheaded a hostage on Tuesday after the government failed to hand over the body of a slain commander for the militant group, a purported spokesman said.

The Afghan government had agreed to hand over the body of Mullah Dadullah, who was killed by US-led forces last month, in return for the release of five local health workers captured by the Islamist insurgents, an official said earlier.

But Shahabuddin Attal, who introduces himself as a Taliban spokesman, said a Dadullah family member had gone to retrieve the body but it was not handed over.

He warned that the guerrillas would chop off the heads of the other hostages should the government again fail to hand over Dadullah's body.

The five health workers were kidnapped in the southern province of Kandahar in March.

Their captors originally demanded the release of Taliban prisoners as ransom and instead this week asked for Dadullah's body, the official said.

"Yesterday it was agreed to," said Abdullah Fahim, a health ministry advisor. "It's their right to have the body of their relative," he added.

The swap was to be handled by local authorities in Kandahar province, Fahim said, which has seen some of the fiercest fighting between Taliban and US-led forces.

Afghan authorities buried Dadullah's body in an undisclosed location soon after he was killed. His death is seen as the biggest blow to the Taliban since they began an insurgency after their overthrow from power in 2001.

Nicknamed as Afghanistan's Al Zarqawi after the slain Al Qaida leader in Iraq, Dadullah was the main architect of suicide bombings, kidnapping of foreigners and Afghans, a series of beheadings and the rise of violence in the south.