Altogether two hostages held by Yemeni Al-Qaeda - American Luke Somers and South African Pierre Korkie - were killed by captors during a US rescue operation, it’s been officially confirmed. Korkie’s death reportedly came a day before his negotiated release.

He was abducted with his wife Yolande in May last year in Yemen's second city, Taiz.

She was freed on 10 January without ransom and returned to South Africa.

Defense Secretary Chuck Hagel, confirming the fatalities, justified the operation to free the hostages.

"There were compelling reasons to believe Mr. Somers' life was in imminent danger," the Pentagon chief told journalists in Kabul.