It was 2:09 a.m. in Kunduz, Afghanistan, on October 3, 2015, when Lajos Jecs was woken from his sleep by a loud explosion. What he was hearing was the first in a series of bombs a US plane was dropping on the hospital he was working at.

Jecs, a nurse for Doctors Without Borders, which is also known by the initials for its French name, MSF, from Hungary had been living and working at the MSF Kunduz Trauma Center in Kunduz, Afghanistan for close to five months. The fighting around the healthcare facility had been growing worse in the past few days. It was so bad that Jecs and his international colleagues had been unable to leave the hospital compound. They’d been sleeping in makeshift quarters in the hospital’s safe room.

It was in the safe room, a building separated from the main hospital, that Jecs went to sleep about 10 p.m. on October 2. Four hours later, he was startled awake by the sound of a bomb exploding. He had heard bombs in Kunduz before, but never this close. The office was rattling and he could hear dirt and debris from the explosions hitting the walls. Jecs took shelter in his room and began trying to call his co-workers in the hospital. None of them picked up, except for one colleague who yelled for help before hanging up.

Some 20 to 30 minutes into the bombing Jecs heard a voice call his name from outside the safe room. When he opened the door he saw one of his Afghan colleagues standing there, covered in blood and with just one arm.

“[That’s] when I realized actually that now we are really, really in danger.” Jecs says. He pulled his colleague into the room and started wishing for the end to come quickly. “Let’s have one bomb here and just finish with it,” he thought.

The bombing attack continued, but the safe house Jecs was in was never hit. When the explosions stopped, Jecs and his colleagues left the building. The sight they saw was terrifying: an orange sky, their hospital in flames, uprooted trees and debris scattered around the compound. Through shelled-out windows they saw patients burning in their beds and heard people screaming inside the hospital as they were burnt alive. Two survivors they tried to help bled to death in front of them.

“I remember that first when I saw the hospital burning, it was like, ‘No. No. It’s not possible [for this] to happen,” Jecs says. “This was just the last thing that I could think could happen to us. I mean because, of course we are in a war zone, fights are happening ... street fights. But to directly target a hospital? ... It was just so unreal.”

MSF says 42 people were killed in the attack, including 14 MSF staff members. Dozens of others were injured.

Jecs says he immediately knew the bombing had been carried out by the United States.

“Why? Because only they had this technology.” Jecs says. He also recognized the sound of the plane that carried out the attack, and says he had heard it before.

The United States has since formally accepted responsibility for the bombing. Last week, the US Department of Defense released the results of an internal investigation into the incident.

“The personnel involved did not know they were striking a medical facility,” Army Gen. Joseph Votel told reporters on Friday. “The intended target was an insurgent-controlled site, which was approximately 400 meters from the Doctors Without Borders trauma center. ... All members of both the ground force and the AC-130 aircrew were unaware that the aircraft was firing on a medical facility throughout the engagement. The investigation ultimately concluded that this tragic incident was caused by a combination of human errors, compounded by process and equipment failures.”

The hospital bombing in Kunduz appears to be part of a disturbing trend. Last week a hospital in Aleppo, Syria, was bombed. No one has claimed responsibility, but only the Russians and the Syrian regime have aircraft in the area. Since the Syrian conflict began in 2011, Physicians for Human Rights has recorded the deaths of 730 medical workers in more than 360 attacks on 256 separate medical facilities.

United Nations Secretary-General Ban Ki-moon on Tuesday said similar attacks are being repeated in other conflict areas, including in Iraq, South Sudan and Yemen.

“Such attacks must end,” Ban Ki-moon said. “When so-called surgical strikes end up hitting surgical wards, something is deeply wrong.”

Doctors Without Borders says it is not satisfied with the internal US investigation into the Kunduz hospital bombing. On Friday the group released a statement calling for an independent investigation.

Jecs echoes his organization’s demand for an independent inquiry.

“Why does this happen? ... I mean, we can go to the moon but we can’t track a sensitive coordinate? ... At least if you are going to have an independent investigation, it could answer a lot of questions, which would be really good for those who lost their loved ones,” Jecs says. “It’s just unbelievable that this is happening now in 2016, that they’re systematically bombing hospitals and killing doctors or health workers. ... It’s like there are no more rules in the war.”

Jecs is disturbed by the trend in attacks on health workers, but he’s not letting that keep him from continuing to work with Doctors Without Borders. Currently he’s working with MSF to provide health care to refugees in Idomeni, Greece. He says he wants to go back to a war zone.

“For me it was like there was only one [bombing] experience in my life — and I really, really hope that this was the last one — and then I could leave Afghanistan. I could go home where there is peace. But for those people living in Afghanistan, in Iraq, Yemen, Syria, they are facing this on a daily basis. It must be so horrible to live under these conditions,” Jecs says. “I have to stay with MSF and help those people who are suffering, especially in war zones, because I know what they are experiencing.”