WASHINGTON - Dr Warren Weinstein, an American aid worker who was kidnapped from Lahore on August 13, 2011, was accidentally killed in a US counter-terrorism operation on the Pakistan-Afghan border, the White House has said.

Also killed was an Italian hostage named Giovanni Lo Porto in the same operation which was carried out in January, along with one American, Ahmed Farouq, who was working with Al-Qaeda, the White House said.

The day Dr Weinstein, a development expert, was captured, three men arrived at the front of Weinstein’s house in Lahore’s Model Town and offered his security guards ‘Sehri’. At the same time, five men forced their way into the house from the back, overpowering Weinstein’s guards and gagging them. The assailants then made their way to Weinstein’s room, where they pistol-whipped him before taking him to a getaway car, according to reports.

Weinstein was reportedly in the final hours of his time in Lahore and had packed his bags to leave Pakistan for good. The 70-year-old was helping to create small businesses in conjunction with the US Agency for International Development (USAID).

In a message released previously in English and Arabic and addressed to Weinstein’s family, Al-Qaeda said it was “not interested in keeping” Weinstein but wanted to exchange him for prisoners in US custody. Lo Porto was an Italian aid worker who went missing in Pakistan in January 2012.

President Barack Obama said he took “full responsibility” for the counterterror missions and offered his “grief and condolences” to the families of the hostages.

Obama defended the legality of the January drone strike that killed the hostages and said there had been no evidence that the two men were present at what the US had determined was an Al-Qaeda compound.

“Based on the intelligence that we had obtained at the time, including hundreds of hours of surveillance, we believed that this was an Al-Qaeda compound, that no civilians were present and that capturing these terrorists was not possible,” Obama said at the White House. “And we do believe that the operation did take out dangerous members of Al-Qaeda.”

Apart from Ahmed Farouq, who the White House said was an American and an Al-Qaeda leader. US officials have also concluded that Adam Gadahn, an American who had served as a spokesman for the terror network, was killed in a separate operation in January.

The White House said neither Farouq nor Gadahn were intentionally targeted in the strikes and the US did not have information indicating their presence at the site of the operations.

A US government official said the drone strikes occurred on Jan 14 and Jan 19 in the border region between Afghanistan and Pakistan. The official was not authorised to discuss details of the attacks and spoke on condition of anonymity.

The president made no mention of Farouq and Gadahn. Instead, he focused his remarks on American Warren Weinstein and Italian Giovanni Lo Porto, who had been held since 2012.

Obama expressed regret for the deaths of the two men and offered condolences to their families. “I realise there are no words that can ever equal their loss,” he said. The mishap represents a major blow to the Central Intelligence Agency (CIA) and its covert drone programme in Pakistan, which President Obama embraced and expanded after coming to office in 2009.

Al-Qaeda extremists are ultimately to blame for the tragic death of Warren Weinstein, the hostage’s wife said Thursday. But Elaine Weinstein said she and her family were disappointed with the US and Pakistani governments’ efforts to secure her husband’s release from his Al-Qaeda captors.

“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 in a statement.

The family was looking forward to the results of a US government investigation into the incident, she said.

“But those who took Warren captive over three years ago bear ultimate responsibility. I can assure you that he would still be alive and well if they had allowed him to return home after his time abroad working to help the people of Pakistan,” she said.

She singled out the Pakistani government in particular for criticism, saying officials did not place a sufficient priority on her husband’s case. And as for Washington, she expressed appreciation to some lawmakers and FBI officials but said “the assistance we received from other elements of the US government was inconsistent and disappointing over the course of three and a half years.”

ITALY CALLS HOSTAGE DEATH ‘TRAGIC AND FATAL ERROR’ BY US

Italy described the death of hostage Giovanni Lo Porto a “tragic and fatal error by our US allies” but said “terrorists” were entirely to blame.

The foreign ministry said in a statement in Rome that Lo Porto had died “because of the tragic and fatal error by our American allies, recognised by President (Barack) Obama”.

It added: “The responsibility for his and Warren Weinstein’s death however... was entirely the terrorists against whom we confirm Italy’s commitment alongside our allies.”