WASHINGTON/Aden - American journalist Luke Somers and a South African hostage were killed on Saturday during a failed attempt by US special forces to free them from Al-Qaeda militants in Yemen.

The news came following a second operation by US and Yemeni forces to free Somers, 33, a year after he was kidnapped by militants in Sana’a. He was apparently shot by his captors during the raid and died of his injuries as he was being flown to an American Navy ship in the region, a US official told the New York Times.

A drone strike at dawn in Yemen’s southern Shabwa province killed nine suspected al-Qaeda fighters in an operation that may have been linked to the raid.

Yemeni extremist group Al-Qaeda in the Arabian Peninsula posted a video Thursday showing Somers and threatening to kill him in three days if the United States didn’t meet the group’s demands, which weren’t specified on the video. On the same video, Somers pleaded for help to save his life.

US Special Operation commandos and Yemeni troops launched the rescue raid to free Somers last month, but he had been quickly moved just days before the operation — though eight other hostages were saved. In a statement, Defence Secretary Chuck Hagel said US special operations forces conducted the raid in central Yemen because the life of journalist Somers, appeared to be in “imminent danger.”

“Both Mr Somers and a second non-US citizen hostage were murdered by Al-Qaeda in the Arabian Peninsula (AQAP) terrorists during the course of the operation,” Hagel said during a visit to Afghanistan. “On behalf of the men and women of the US armed forces, I extend our condolences, thoughts and prayers to their families and loved ones.”

President Barack Obama condemned the “barbaric murder” of Somers, saying he had authorised the joint rescue operation because the life of the 33-year-old photojournalist was believed to be “in imminent danger”.

“The callous disregard for Luke’s life is more proof of the depths of AQAP’s depravity, and further reason why the world must never cease in seeking to defeat their evil ideology,” Obama said in a statement.

He said he had authorised the attempted rescue and said the United States would “spare no effort to use all of its military, intelligence and diplomatic capabilities to bring Americans home safely, wherever they are located”.

US Secretary of State John Kerry said the rescue operation was only approved because of information that lives were at imminent risk. “Earlier this week, AQAP released a video announcing that Luke would be murdered within 72 hours. Along with other information, there was a compelling indication that Luke’s life was in immediate danger,” Kerry said.

South African hostage Pierre Korkie was also killed in the raid, according to a charity that had been negotiating his release. The Gift of the Givers said that Korkie’s death came a day before he was due to be freed after more than a year in captivity. “The psychological and emotional devastation to (his wife) Yolande and her family will be compounded by the knowledge that Pierre was to be released by Al-Qaeda tomorrow,” it said.

The South African couple, who had worked as teachers in Yemen for four years, were seized by Al-Qaeda in May 2013 in the city of Taez. The wife was released in January following mediation by Gift of the Givers.

The charity said logistical arrangements had already been put in place to fly Pierre Korkie out of Yemen under diplomatic cover after negotiations.

“It is even more tragic that the words we used in a conversation with Yolande at 5.59 this morning was ‘the wait is almost over’. “Three days ago we told her ‘Pierre will be home for Christmas’. We certainly did not mean it in the manner it has unfolded.”

Ten militants were killed in the joint operation in Shabwa province in southeast Yemen, Yemen’s defence ministry said.

A tribal leader said soldiers were seen parachuting into the area and residents reported heavy clashes.

Obama said that since the abduction of Somers 15 months ago, Washington had been using “every tool at our disposal” to try to secure his release. “Luke was a photojournalist who sought through his images to convey the lives of Yemenis to the outside world,” Obama added.

“He came to Yemen in peace and was held against his will and threatened by a despicable terrorist organisation.”

Lucy Somers, the photojournalist’s sister, told the Associated Press that she and her father learned of her brother’s death from FBI agents at 0500 GMT (12 am EST) Saturday. “We ask that all of Luke’s family members be allowed to mourn in peace,” she said from London.

Washington has a long-standing policy of not negotiating with hostage-takers or paying ransoms.

According to Yemen’s defence ministry, Al-Qaeda moved hostages, including the US journalist, a Briton and a South African, days before that US-Yemeni raid in southeastern Hadramawt province.

The whereabouts of the Briton are unknown. Yemeni officials said eight other hostages were freed in the earlier operation. Yemen is a key US ally in the fight against Al-Qaeda, allowing Washington to conduct a long-standing drone war against the group on its territory.

AQAP is considered by Washington to be the most dangerous affiliate of Al-Qaeda. The execution threat by AQAP followed the murder of five Western hostages since August by the Islamic State group that controls parts of Syria and Iraq.

Two US journalists, James Foley and Steven Sotloff, American aid worker Peter Kassig and British aid workers Alan Henning and David Haines were all beheaded. Al-Qaeda has exploited instability in impoverished Yemen since a 2011 uprising forced president Ali Abdullah Saleh to step down. In recent years there had been a growing number of abductions in Yemen by Al-Qaeda.