CAIRO -- A Saudi militant believed killed in the U.S. drone strike in Yemen constructed the bombs for the al-Qaida branch's most notorious attempted attacks -- including the underwear-borne explosives intended to down a U.S. aircraft and a bomb carried by his own brother intended to assassinate a Saudi prince.
The death of Ibrahim Hassan al-Asiri would make the Friday drone strikes on a convoy in the central deserts of Yemen one of the most effective single blows in the U.S. campaign to take out al-Qaida's top figures.
The strike also killed Anwar al-Awlaki, a Yemeni-American cleric who had been key to recruiting for the militant group and a Pakistani-American, Samir Khan, who was a top English-language propagandist.
But Christopher Boucek, a scholar who studies Yemen and al-Qaida, said al-Asiri's death would "overshadow" that of the two Americans due to his operational importance to al-Qaida in the Arabian Peninsula, the Yemen-based group that is considered the most active branch of the terror network.
Late Friday, two U.S. officials said intelligence indicated al-Asiri was among those killed in the strike. The officials spoke on condition of anonymity because al-Asiri's death has not officially been confirmed.
The 29-year-old al-Asiri was one of the first Saudis to join the Yemen-based al-Qaida branch and became its key bombmaker, designing the explosives in two attempted attacks against the United States.
His fingerprint was found on the bomb hidden in the underwear of a Nigerian man accused of trying to blow up Northwest Airlines Flight 253 over Detroit on Christmas 2009, according to U.S. counterterrorism officials. The attack failed because the would-be bomber, Umar Farouk Abdulmutallab, botched detonating the explosives and ended up burning himself before being tackled by passengers.
The explosives used in that bomb were chemically identical to those hidden inside two printers that were shipped from Yemen last year, bound for Chicago and Philadelphia in a plot claimed by al-Qaida. The bombs were intercepted in England and Dubai.
In perhaps his most ruthless operation, al-Asiri turned his younger brother, Abdullah, into a human bomb in a 2009 attempt to kill Saudi Prince Mohammed bin Nayef, the kingdom's top counterterrorism official and son of its interior minister.