The US forces conducted an operation targeting al-Qaeda at the border of Pakistan and Afghanistan.
Two innocent citizens of Italy and the US were killed.
Obama accepted the fact that hostages from these countries were inadvertently killed.
"It is a cruel and bitter truth that in the fog of war generally, and our fight against terrorists specifically, mistakes, sometimes deadly mistakes can occur," Obama said yesterday at his press conference in the White House.
Warren Weinstein and Giovanni Lo Porto were held by al-Qaeda since 2011 and 2012 respectively.
White House press secretary Josh Earnest also expressed his deepest apologies to the families of the victims.
According to him, there were also killed an American Ahmed Farouq, who was al- Qaeda leader and Adam Gadahn, an American who served as a prominent spokesman for the group. White House noticed that the two leaders were not targeted specifically, as the US "did not have information indicating their presence at the sites of these operations."
Obama claimed that as being a president and commander-in-chief, he takes full responsibility for all counterterrorism operations.
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