This is Russian radio traffic ... ... to an air force pilot on a bombing mission over Syria. But these coordinates aren’t for a military target. They point to this underground hospital. Moments later, the pilot bombs it. Nabad al Hayat is one of more than 50 health care facilities bombed in Syria since April, as president Bashar al-Assad seeks to retake the last pocket of opposition with a ferocious onslaught of air power. Observers have long suspected that Russia bombs hospitals. But no one has been able to prove it — until now. The Times has assembled a large body of evidence from multiple sources that directly implicates Russia in four hospital attacks in just 12 hours: one day that’s a microcosm of how health care has been crippled in parts of Syria. We collected four main types of evidence: First, flight logs. For years, a network of plane spotters has tracked air force activity over Syria to warn civilians of incoming attacks. They record sightings of fighter jets and listen in on open radio communications between pilots and air traffic controllers. We received months of those flight logs, which tell us where and when the Russian air force was flying. Second, we obtained thousands of recordings of those radio transmissions as Russian pilots operate in the skies above northwest Syria. We spent weeks translating and deciphering their code words to understand how they carry out airstrikes: A pilot receives coordinates for a target. He confirms the target is locked. The pilot calculates the minute he will strike. The dispatcher gives the green light. And the pilot reports back, saying, “Srabotal” — “I worked it.” This gives us the clearest picture yet of how and when Russia bombed targets. Third, we analyzed hours of videos of these strikes, which gave us clues about the type of weapons used. We reviewed that footage with experts on the Russian air force. And fourth, we established the time these attacks happened by interviewing medics, obtaining incident reports and examining social media postings. The times of the attacks matched up with sightings of Russian planes and recordings of pilots carrying out strikes. Our detailed findings show how Russia repeatedly violated one of the oldest laws of war. We’ll walk through those attacks on May 5 to show how the evidence stacks up. Let’s start with Nabad al Hayat, where local journalists were warned it could be bombed and filmed the attack. First, the strike time. An incident report said it was hit around 2:40 p.m. Second, flight logs: Spotters in the area reported a Russian jet flying overhead just minutes before the attack. Third, radio recordings: The Russian pilot and air traffic controller are heard preparing the attack minutes before 2:40 p.m. Those coordinates point directly at the underground hospital, and at 2:40, the pilot confirms the strike. Fourth, analysis of the strike itself: Three projectiles fall in quick succession and very precisely, within around 100 feet of each other. They also appear to explode after a slight delay once they penetrate the ground. Military experts told us these are the hallmarks of a precision strike, something the Syrian air force is not currently capable of, only the Russians. Luckily, the hospital was empty, because days before, staff had received warnings from plane spotters of possible attacks. It had in the past treated hundreds of patients every month, but it remains out of service today. Around three miles away, Doctors in Kafr Nabl were treating patients that afternoon when this single hospital was hit four times in 18 minutes. We spoke to one of its doctors. Again, the evidence from 5:30 p.m. points to Russia. Spotters reported both Russian and Syrian jets flying overhead. Next, radio messages record a Russian pilot making four strikes at that very time. At 5:30 p.m., the pilot says: At 5:35 p.m.: 5:40 p.m.: And 5:48 p.m.: Four strikes in all, each around five minutes apart, at the exact time witnesses reported the attack. And last, the weapon: Three precision strikes hit the hospital’s entrance. Experts told us it’s highly unlikely Syrian jets could do this. Because the hospital was dug deep underground, only one person was killed in the attack — though many were injured. The bombing didn’t stop there. Kafr Zita Cave Hospital was hit at 3:15 p.m. The hospital director reported it in a WhatsApp message to a colleague that day. Again, flight logs record a Russian jet near Kafr Zita around that time, and at 3:15, a Russian pilot confirms a strike. That night, Al Amal Orthopedic Hospital was hit. Again, only Russian jets were recorded flying in the area, and a Russian pilot confirms the strike around 2 a.m. Health care facilities have been attacked more than 600 times in the course of Syria’s war. It’s a deliberate strategy to make civilian life unbearable in opposition strongholds. In response to The Times, Russian officials denied responsibility and said they carry out precision strikes only on what they call “accurately researched targets.” But these hospitals were on a no-strike list that Russia received from the United Nations. And The Times confirmed with medical groups that they were operational on the day of the attacks. Russia and Syria should have known they were off limits. By law, it’s their responsibility to avoid hitting them. But this evidence paints a damning portrait of a permanent member of the U.N. Security Council committing gross violations in just one day of Russia’s four-year air campaign in Syria. Hey, this is Malachy, and I lead the team who worked on this video. We spent thousands of hours putting this investigation together, and we knew we had important new details to share when we got audio recordings of a Russian pilot receiving the coordinates for a hospital and then bombing it. The source of the audio asked to remain anonymous for their safety. But the evidence they provided was irrefutable. We do this work to find the truth and hold people in power to account. Thank you for watching.