Officials say Ibrahim Hassan al-Asiri was involved in several plots to attack airliners.

US President Donald Trump confirmed on Thursday that top al-Qaeda bomb-maker Ibrahim Hassan al-Asiri, who had specialised in making explosives that evaded airport security checks, was killed two years ago in a US operation in Yemen.

Officials said last year that they were confident al-Asiri, a prominent member of al-Qaeda in the Arabian Peninsula (AQAP), had been killed in 2017, but others had cautioned at the time that the evidence was not conclusive.

The Associated Press reported in 2018 that al-Siri and several associates had been killed in a US drone attack in the governante of Marib in eastern Yemen, citing tribal leaders and al-Qaeda-linked sources. The death was considered a blow the group’s ability to attack Western targets.

The White House confirmed the death in a statement on Thursday, without offering further details of the operation or explaining why it was only now making the announcement.

“Al-Asiri’s death significantly handicapped al-Qa’ida [sic] in the Arabian Peninsula. The United States will continue to hunt down terrorists like al-Asiri until they no longer pose a threat to our great Nation,” the White House statement said.

Failed attacks

Al-Asiri became a prominent bomb-maker after AQAP formed in 2009, following the merger of the Yemeni and Saudi branches of al-Qaeda.

Thursday’s White House statement also confirmed al-Asiri’s role in several prominent failed attacks carried out by the group.

The Saudi Arabian national was long believed to have masterminded a failed attack on a US-bound airliner on Christmas Day in 2009. In that attempt, 23-year-old Umar Farouk Abdulmutallab, a Nigerian citizen, tried to detonate an underwear bomb, which the White House confirmed was built by al-Asiri, on a passenger jet as it flew over Detroit, Michigan, from Amsterdam.

When the explosive failed to detonate properly, Abdulmutallab was tackled and restrained by another passenger.

Al-Asiri created a more refined underwear bomb for a foiled attempt to target another airline in 2012, according to the White House.

Al-Asiri, who studied chemistry in the Saudi capital of Riyadh, had also designed bombs disguised as printer cartridges that al-Qaeda attempted to send to the US via cargo planes in October of 2010. However, the bombs were found while the planes were making stopovers in the United Kingdom and Dubai.

The explosive maker had also recruited his brother, Abdullah al-Asiri, as a suicide bomber in the attempted assassination of former Saudi Crown Prince Mohammed bin Nayef in 2009.

US intelligence, in recent years, believed that al-Asiri and his associates were constantly working to improve their bomb designs so that they could get past airport security, reportedly prompting the US to ban all laptops and large tablets from hand luggage on flights from the Middle East in 2017.