Mohammed al-Gherari lost five family members, including a young niece and nephew, when NATO accidentally struck their compound in the Libyan capital as they slept.

Nearly a year later, his grief is compounded by threats and allegations from neighbors who believe he and others who survived the attack were harboring a regime loyalist or hiding weapons for Moammar Gaddafi's forces.

At least 72 civilians, a third of them under the age of 18, were killed by airstrikes, according to a report released Monday by Human Rights Watch — one of the most extensive investigations into the issue. The New York-based advocacy group called on the Western alliance to acknowledge the casualties and compensate survivors.

The decision by the United States and its allies to launch an air campaign that mainly targeted regime forces and military infrastructure marked a turning point in Libya's civil war, giving rebels a fighting chance. But Gaddafi's government and allies in Russia and China criticized the alliance for going beyond its UN mandate to protect civilians.

The number of Libyans killed or injured in airstrikes also emerged as a key issue in the war as Gaddafi's regime frequently exaggerated figures and refused to comment on most claims, insisting all targets were military.

At one point, Libya's Health Ministry said 856 civilians had been killed in 's campaign, which began in March 2011, weeks after the uprising against Gaddafi that erupted with peaceful protests evolved into a civil war.

The UN-appointed International Commission of Inquiry on Libya said earlier this year that at least 60 civilians had been unintentionally killed and recommended further investigation.

Based on investigations conducted in Libya from August 2011 through this April, Human Rights Watch established that 28 men, 20 women and 24 children — 72 civilians in all — had been killed in eight bombings in Tripoli, Zlitan, Sorman, Bani Walid, Gurdabiya and Gaddafi's hometown of Sirte.

The advocacy group acknowledged the figure was relatively low considering the extent of the seven-month campaign, which the alliance has said included 9,600 strike missions and destroyed about 5,900 military targets. It ended after Gaddafi's death in late October.

The group said it had documented several cases in which there clearly was no military target and criticized for failing to acknowledge the deaths or to examine how and why they occurred.

In Brussels, said it had carried out the bombing campaign with "unprecedented care and precision" and had fulfilled the requirements of international humanitarian law.

" did everything possible to minimize risks to civilians, but in a complex military campaign, that risk can never be zero," spokeswoman Oana Lungescu said on Monday. "We deeply regret any instance of civilian casualties for which may have been responsible."

She said the alliance had looked into each allegation of civilian casualties.

"We have reviewed all the information we hold as an organization and confirmed that the specific targets struck by were legitimate military targets," Lungescu said.

The alliance did not have troops on the ground during or after the conflict who could have independently checked the results of its airstrikes.

HRW recommended that make public information about the intended military targets in cases where civilians were wounded or killed and provide "prompt and appropriate compensation" to families who suffered from the attacks.

The strike against al-Gherari's compound on June 19, 2011, was a rare case in which the Brussels-based alliance admitted it had made a mistake. "It appears that one weapon did not strike the intended target and that there may have been a weapons system failure which may have caused a number of civilian casualties," said in a statement.

The Libyan government rushed a group of foreign journalists based in Tripoli to the site, eager to use the deaths as propaganda against the West. Children's toys, teacups and dust-covered mattresses could be seen amid the rubble, and the journalists were shown the bodies of at least four people said to have been killed in the strike, including the two young children.

Al-Gherari said government officials disappeared shortly after the fanfare ended and the family received no compensation or financial assistance from either side. Meanwhile the acknowledgment, which did not provide details, failed to satisfy neighbors who continued to accuse the family of harboring a regime figure.

"I want to present a full explanation that the reason was a mistake because we're still facing accusations that Gaddafi or a higher regime figure was there and that's why our house was targeted," he said in an interview with The Associated Press.

He said five people were killed, including his 2-year-old nephew and a 7-month-old niece.

Lungescu, the spokeswoman, said the June 19 strike targeted a missile site in Tripoli but that one weapon malfunctioned and was unable to determine where it landed. "A review concluded it was possible that the failed weapon may have hit the house of the al-Gherari's family, which was not the intended target," she said.

Human Rights Watch said it visited the site in the Souk el-Juma neighborhood in August and December and "did not see any evidence of military activity such as weapons, ammunition or communications equipment." It also said satellite imagery showed no signs of military activity at the home.

The deadliest attack recorded by the rights group was in the rural village of Majer, south of the former rebel stronghold of Zlitan.

The first bomb hit a large, two-story house owned by Ali Hamid Gafez, a 61-year-old farmer. It was crowded with people who had fled the fighting in nearby areas. That was followed by three more bombs that killed 34 people killed, including many who had rushed to the site to help after the earlier explosions.

Human Rights Watch said it visited the area the day after the Aug. 8, 2011, strikes and found no evidence of military activity, although it did find one military-style shirt in the rubble.

"I'm wondering why they did this, why just our houses," one of the residents, Muammar al-Jarud, was quoted as saying in the report. "We'd accept it if we had tanks or military vehicles around, but we were completely civilians and you can't just hit civilians."