The White House announced on Thursday that American Dr. Warren Weinstein and Italian Giovanni Lo Porto were killed in a January drone strike on an al-Qaeda compound located in the border region of Afghanistan and Pakistan.
Weinstein had been held by the terrorist group since 2011, while Lo Porto was taken hostage in 2012.
Weinstein had been in Pakistan on a four-year aid project funded by the US government. Two days before he was due to return to the United States, he was captured in his home by al-Qaeda operatives, the National Journal reported.
President Barack Obama said he spoke with Weinstein's wife, Elaine, who released a statement after the White House announcement.
"We were so hopeful that those in the US and Pakistani governments with the power to take action and secure his release would have done everything possible to do so, and there are no words to do justice to the disappointment and heartbreak we are going through," she said.
She thanked lawmakers from her home state of Maryland – Rep. John Delaney, Sen. Barbara Mikulski, and Sen. Bob Cardin – and several FBI officials "for their relentless efforts to free my husband."
But she also criticized the federal government's response to her husband's situation.
"Unfortunately, the assistance we received from other elements of the US government was inconsistent and disappointing over the course of three and a half years," Elaine said. "We hope that my husband's death and the others who have faced similar tragedies in recent months will finally prompt the US government to take its responsibilities seriously and establish a coordinated and consistent approach to supporting hostages and their families."
The White House said it "had no reason to believe" either hostage was present at the targeted al-Qaeda compound.
President Obama said he takes "full responsibility" for the deaths of Weinstein and Lo Porto, adding that he had directed his national security team "to do everything possible" to locate Weinstein after he was kidnapped.
Ahmed Farouq, an American-born al-Qaeda leader, was killed in the same operation that took the lives of Weinstein and Lo Porto. Another American member of al-Qaeda, Adam Gadahn, is also believed to have been killed in January, in a separate counterterrorism operation.