Charlie Burbridge, the managing director of G4S Risk Management Group, said 32 employees of the company were also wounded in the attack, five of them seriously. "Our thoughts at this difficult time are with the loved ones of those who have died and been injured, and our brave team in Afghanistan who have lost colleagues and friends," Burbridge said in a statement.
The attack started with a suicide bomber who rammed his explosive-packed truck into the gate of the G4S compound in eastern Kabul on Wednesday evening, followed by an hours-long gunbattle with insurgents armed with grenades and automatic rifles who stormed the compound building.
The Taliban, who claimed responsibility for the attack, said it was in retaliation for a U.S. airstrike in southern Helmand province hours earlier that killed 30 people, many of them civilians. Afghan officials revised the initial number of 10 reported killed in the Kabul assault to six. The public health ministry spokesman, Wahid Majroh, said four attackers had also died, leading to the confusion, but he did not identify any of the casualties.
The suicide blast left a giant crater in its wake and blew out windows in nearby buildings. Jan Agha, a police officer at the site of the explosion Thursday, recalled the gunbattle that lasted into the night as ambulances ferried the victims to hospitals amid the chaos.
Taliban spokesman Zabihullah Mujahid said the insurgents had killed 10 foreigners but the Taliban often exaggerate their claims. All the attackers died in the assault. After the attack in Helmand, a local official, Attahullah Afghan, said most of the civilian casualties there — which included men, women and children — came when an airstrike struck a house in the central Helmand River valley, a Taliban heartland.
U.S. officials said it happened in Helmand's Garmsir district. U.S. military spokeswoman in Kabul, Sgt. 1st Class Debra Richardson said the airstrike was called in by Afghan special security forces who were conducting an operation with the assistance of U.S. advisers.
"At the time of the strike, the ground force was unaware of any civilians in or around the compound; they only knew that the Taliban was using the building as a fighting position," she said in an email.
A statement from the governor's office in Helmand confirmed that 16 Taliban were killed. It said an investigation was underway to determine the number of civilian casualties. The statement also said the militants had stockpiled ammunition in the area of the operation, which could have caused civilian casualties. There was also a car packed with explosives that ignited during the strike, the statement added.
The attacks were the latest in a series of brutal and near-daily Taliban assaults throughout the country. The Taliban view the U.S.-backed government in Kabul as a dysfunctional Western puppet and have refused repeated offers to negotiate with it.
The fighting came as Afghan President Ashraf Ghani was in Geneva, attending a two-day U.N.-backed conference that ended Wednesday and that focused on development, security and peace efforts in the war-battered country.
Associated Press writers Kathy Gannon in Islamabad and Jill Lawless in London contributed to this report.