Last Updated Dec 6, 2014 10:08 PM EST
SANAA, Yemen -- An American photojournalist and a South African teacher held by al Qaeda militants in Yemen were killed Saturday during a U.S.-led rescue operation that President Obama said he ordered because of "imminent danger" to the U.S. hostage.
According to a senior administration official, the U.S. believes a militant shot the two men during the raid, CBS News correspondent Margaret Brennan reports.
South African Pierre Korkie and American Luke Somers were still alive but had recently been wounded when the SEALs pulled them from a building on the group's compound and got them aboard an Osprey aircraft with a surgeon, according to the official. One of the hostages died en route to a U.S. Navy ship while the other died onboard the ship.
The operation lasted around 30 minutes and happened on what the official described as "challenging terrain" in southern Shabwa province. The operation happened at a compound in a remote area with other compounds in the vicinity. The most difficult part of the raid lasted between five and 10 minutes.
A 40-person team of SEALs landed nearby the compound and moved in, the official said. As the SEALs neared the compound, they lost the "element of surprise" and a firefight ensued. The SEALs eliminated the threat.
However, during that time, they saw a single fighter move into the building where they believed the hostages were being held, the official said. He was in there long enough to shoot two people. By the time the SEALs made it to the building, the militants had fled.
Six militants were killed during the raid, the official said. As far as the official knew, none of the SEALs were injured and there was no evidence of civilian casualties.
The second rescue attempt in less than two weeks to free Somers was prompted by a video posted online earlier in the week in which Al Qaeda in the Arabian Peninsula threatened to kill Somers within 72 hours.
But an aid group helping negotiate Korkie's release said he was to be freed Sunday and his wife was told that "the wait is almost over."
In a statement, Mr. Obama did not address Korkie by name, only saying he "authorized the rescue of any other hostages held in the same location as Luke." The South African government did not immediately comment on Korkie's death.
Information "indicated that Luke's life was in imminent danger," Mr. Obama said. "Based on this assessment, and as soon as there was reliable intelligence and an operational plan, I authorized a rescue attempt."
Officials said Mr. Obama authorized the rescue mission Friday morning and was informed that evening about the outcome.
Lucy Somers, the photojournalist's sister, told The Associated Press that she and her father learned of her 33-year-old brother's death from FBI agents at 12 a.m. EST Saturday.
"We ask that all of Luke's family members be allowed to mourn in peace," she said from Kent, near London.
Yemen's national security chief, Maj. Gen. Ali al-Ahmadi, said the militants planned to kill Luke Somers on Saturday, and that prompted the joint mission.
"Al Qaeda promised to conduct the execution (of Somers) today so there was an attempt to save them but unfortunately they shot the hostage before or during the attack," al-Ahmadi said at a conference in Manama, Bahrain.
The operation began before dawn Saturday in a province that is a stronghold of al Qaeda's branch in Yemen. U.S. drones struck first the Wadi Abdan area first, followed by strafing runs by jets before Yemeni ground forces moved in, a Yemeni security official told the AP. Helicopters flew in more forces to raid the house where the two men were held, he said.
At least nine al Qaeda militants were killed in an initial drone strike, another security official told the AP. Both spoke on condition of anonymity because they were not authorized to speak to reporters.
U.S. Defense Secretary Chuck Hagel said the rescue mission was "extremely well executed, and was complicated and risky. The two men "were murdered by the AQAP terrorists during the course of the operation," Hagel said during a visit to Afghanistan.
The rescue mission was the second by U.S. and Yemeni forces searching for Somers, among the roughly dozen hostages believed held by al Qaeda militants in Yemen.
On Nov. 25, American special operations forces and Yemeni soldiers raided a remote al Qaeda safe haven in a desert region near the Saudi border, freeing eight captives, including Yemenis, a Saudi and an Ethiopian. Somers, a Briton and four others had been moved days earlier, officials later said.
Following that first raid, al Qaeda militants released a video Thursday that showed Somers. The group threatened to kill him in three days if the United States did not meet unspecified demands or if another rescue was made.
Somers was kidnapped in September 2013 as he left a supermarket in the Yemeni capital, Sanaa, said Fakhri al-Arashi, chief editor of the National Yemen, where Somers worked as a copy editor and a freelance photographer during the 2011 uprising in Yemen.
Before her brother's death, Lucy Somers released an online video describing him as a romantic who "always believes the best in people." She ended with the plea: "Please let him live."
In a statement, Somers' father, Michael, also called his son "a good friend of Yemen and the Yemeni people" and asked for his safe release.
Korkie was kidnapped in the Yemeni city of Taiz in May 2013, along with his wife, Yolande. Militants later released her after a nongovernmental group, Gift of the Givers, helped negotiate for her freedom. Those close to Korkie said al Qaeda militants demanded a $3 million ransom for his release.
"The psychological and emotional devastation to Yolande and her family will be compounded by the knowledge that Pierre was to be released by al-Qaida tomorrow," Gift of Givers said in a statement Saturday.
"A team of Abyan leaders met in Aden this morning and were preparing the final security and logistical arrangements, related to hostage release mechanisms, to bring Pierre to safety and freedom. 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.'"
Somers, who was born in Britain, earned a bachelor's degree in creative writing while attending Beloit College in Wisconsin from 2004 through 2007.
"He really wanted to understand the world," said Shawn Gillen, an English professor and chairman of Beloit College's journalism program who had Gillen as a student.
Fuad Al Kadas, who called Somers one of his best friends, said Somers spent time in Egypt before finding work in Yemen. Somers started teaching English at a Yemen school but quickly established himself as a one of the few foreign photographers in the country, he said.
"He is a great man with a kind heart who really loves the Yemeni people and the country," Al Kadas wrote in an email from Yemen. He said he last saw Somers the day before Somers was kidnapped.
"He was so dedicated in trying to help change Yemen's future, to do good things for the people that he didn't leave the country his entire time here," Al Kadas wrote.
Al-Arashi, his editor at the National Yemen, recalled a moment when Somers edited a story on other hostages held in the country.
"He looked at me and said, 'I don't want to be a hostage,'" al-Arashi said. "'I don't want to be kidnapped.'"