KABUL, Afghanistan -- Afghan officials released harrowing new details on Thursday about an attack in a western province where assailants shot everyone in their path, sending terrified people jumping from windows trying to escape the assailants who killed at least 46 civilians and security forces.
Civilians have frequently been caught up in the fighting between militants and Afghan and U.S.-led combat forces, but the U.N. condemned Wednesday's attack, saying civilians were deliberately targeted at the courthouse and other government offices in Farah province. Two judges, six prosecutors, administration officers and cleaners working at the site were among the dead, the U.N. said.
Also Thursday, NATO reported that an American F-16 fighter jet had crashed in eastern Afghanistan, killing the U.S. pilot. The U.S.-led military coalition did not release further details about Wednesday's crash.
"While the cause of the crash is under investigation, initial reporting indicates there was no insurgent activity in the area at the time of the crash," the coalition said in a statement.
Illustrating other dangers, an airstrike by U.S.-led forces mistakenly killed four policemen and two brothers as their car was being searched at a checkpoint in eastern Afghanistan, an Afghan official said Thursday.
The strike occurred in the Deh Yak district of Ghazni province, according to district chief Fazel Ahmad Toolwak. He said NATO troops were fighting Taliban militants about 10 kilometers (six miles) away, but those killed in the strike were not involved in that battle.
A NATO spokesman, U.S. Army Maj. Adam Wojack, said the international military coalition was looking into the report, adding it "takes all allegations of this type seriously."
According to a recent U.N. report, 2,754 Afghan civilians were killed last year -- down 12 percent from 3,131 killed in 2011. But the number killed in the second half of last year rose, suggesting that Afghanistan is likely to face continued violence as the Taliban and other militants fight for control of the country as foreign forces continue their withdrawal.
The U.N. said the Taliban and other insurgents were responsible for 81 percent of the civilian deaths and injuries last year, while 8 percent were attributed to pro-government forces. The remaining civilian deaths and injuries could not be attributed to either side.
The number of casualties blamed on U.S. and allied forces decreased by 46 percent, with 316 killed and 271 wounded last year. Most were killed in U.S. and NATO airstrikes, although that number, too, dropped by nearly half last year to 126, including 51 children.
The Taliban claimed responsibility for the attack in Farah, the capital of the province of the same name near the border with Iran.
The hospital in Farah was so overwhelmed with casualties that helicopters had to ferry some of the wounded to other hospitals in nearby areas.
Provincial Gov. Akram Akhpelwak said two more people had died from the attack, raising the death toll to 55 - 36 civilians, 10 Afghan security forces and nine attackers. More than 100 people also were wounded, he said.
One of the province's members of parliament, Humaira Ayobi, said one elderly man was found hiding in a bathroom, afraid to come out.
"Farah is a city of sadness," she said in a telephone call after attending a funeral for some of the victims. "The stores are closed. There's no traffic in the streets."
The attack began when two suicide bombers detonated an explosives-laden vehicle near the courthouse, shattering windows and devastating several buildings. Seven others jumped out of the pickup and ran toward the courthouse and attorney general's office, prompting an eight-hour gunbattle that left many buildings pockmarked from bullets and rocket-propelled grenades.
Ayobi said the attackers went from room to room shooting people, including nearly two dozen people who had taken refuge in a basement. She also said two judges were singled out to be killed in a separate room, and that their bodies were burned.
The attackers were wearing military-style uniforms easily bought in Afghan markets and had painted a pickup in camouflage to disguise it as an Afghan National Army vehicle so it could bypass checkpoints, she said.
An Associated Press photo shows a group of soldiers standing over the body of one of the slain attackers who was lying in a pool of blood and wearing a uniform nearly identical to theirs.
Local officials said Wednesday that they believed the attackers were trying to free 15 Taliban prisoners who were about to stand trial. But Ayobi said the initial target might have been the governor's compound until heavy security there forced the attackers to redirect themselves to the courthouse.
In New York, the U.N. Security Council condemned the attack "in the strongest terms" and called for the perpetrators, organizers and financiers to be brought to justice. The council reiterated its "serious concern at the threats posed by the Taliban, Al-Qaida and illegal armed groups to the local population, national security forces, international military and international assistance efforts in Afghanistan."