A United States drone attack that killed 10 civilians in Afghanistan’s capital Kabul in August was not caused by misconduct or negligence, AP reported on Wednesday citing an internal Pentagon review.

On August 29, the US had launched an unmanned drone strike on a man in a car who they believed was an Islamic State-Khorasan operative. The terror group had claimed responsibility for the bombing at the Kabul airport on August 28 in which 169 Afghans and 13 US Army personnel were killed.

However, discrepancies surfaced in the reports. An investigation by The New York Times questioned the US’ version of events. Central Command head Frank Mckenzie in September admitted to shooting down the wrong target with a hellfire missile.

“The investigation found no violation of law, including the law of war,” said Lieutenant General Sami Said on Wednesday, according to The Guardian. “Execution errors combined with confirmation bias and communication breakdowns led to regrettable civilian casualties. It was an honest mistake.”

The lieutenant general said that the drone strike should be seen in the context of the circumstances – US forces were stressed by the information about the threat to troops and forces at the Kabul airport, AP reported.

The US and its allies withdrew its troops from Kabul at the end of August, bringing an end to 20 years of war that began after the September 11, 2001 al-Qaeda attacks on New York City and Washington.

Said’s report stated that during the evacuation the intended target of the strike, the vehicle, its contents and occupants were assessed. “What likely broke down was not the intelligence but the correlation of that intelligence to a specific house,” the lieutenant general said.

Said explained that there was not one point in the series of events or one person is to be blamed for the drone strike, The Guardian reported. He also said it was not his responsibility to punish a particular person for the error.

The report was endorsed by Defense Secretary Lloyd Austin, according to AP. He made several suggestions that were passed on to officers at US Central Command and US Special Operations Command.

The review recommended prevention of “confirmation bias”, wherein troops make immediate decision to strike, assuming that what they are seeing aligns with information from the intelligence unit.

Democratic Congressman Adam Schiff, who is the chairman of the House Permanent Select Committee on Intelligence, said he was “unconvinced” that the Pentagon reports “provides for real accountability”, according to Al Jazeera.

“From what the Intelligence Committee has learned of this strike and the events leading up to it, as well as statements made in its immediate wake, I have serious concerns that are unaddressed by what has been put forward publicly,” Schiff said.

Meanwhile, the contents of the report are not being made public because it contains information on methods used by the US to conduct the drone strikes, Al Jazeera reported.