Osama bin Laden's son Sa'ad was probably killed by a US missile strike in Pakistan earlier this year, reports have said.
Sa'ad bin Laden was a prominent figure in the murky relationship between Iran and al Qaeda.
It was believed he went to Pakistan after spending a number of years under house arrest in Iran, US intelligence officials said in January.
But a missile fired from a US drone aircraft is believed to have killed him sometime this year, US National Public Radio said citing an unnamed US counter-terrorism official.
