As on most nights, Russian forces were targeting cities across Ukraine, threatening civilians and vital infrastructure. Gliding across the border were two guided bombs headed in the direction of Kharkiv, Ukraine’s second-largest city.
At a secret facility deep below ground, Ukrainian specialists were watching and waiting, fingers at the ready. If the city was the target, they would need to act even before the military’s air defenses engaged, switching on citywide sirens to warn residents to take cover.
Such sirens are an eerie soundtrack to the war, a shared experience for Ukrainians in towns and cities across the country. But how they actually work — and who is behind them — has been a closely guarded secret.
Last month, the city of Kharkiv gave The New York Times rare access to its emergency-response center, where teams of civilian specialists save countless lives with the flip of a switch and the push of a big red button on a computer screen. The work is not automated, as many Ukrainians assume.
“I try to do everything as quickly as possible,” said Dmytro, 23, one of the specialists, who for security reasons asked to be identified only by his first name. That way, he said, “people have more time to hide.”
Located just 20 miles from the Russian border, Kharkiv comes under frequent attack, with the scars of missile and bomb attacks covering the city. There were 1,826 air-raid alarms last year, an average of five a day.
After years of war, many residents were becoming complacent about the threat. Some were still running to basements or subway stations. Others sheltered at home, moving into hallways, bathrooms or between two strong walls. And some, knowing that strikes anywhere in the Kharkiv region — one of Ukraine’s largest — set off air-raid alarms for the city itself, simply took to ignoring the sirens.
That was one reason that the mayor, Ihor Terekhov, ordered up a differentiated system, the first of its kind in Ukraine, so that sirens would sound only when the city itself was being targeted. Since the new system went into effect in early 2025, the city has had half the number of alarms as the broader region and no cases in which sirens sounded too late.
“It paid off, it definitely paid off,” Bohdan Hladkykh, head of the city’s Department of Emergency Situations, said of the new system, which cost half a million dollars.
While the Kyiv region is adopting a similar system, Mr. Hladkykh called it “regrettable” that other cities had not followed Kharkiv’s example.
The highly secured situation center lies at the heart of the new system, a 24/7 operation staffed with 12-hour shifts.
The “chief specialist” is the person responsible for setting off the sirens. A supervisor sits alongside.
The specialist’s workstation has two mouses. One performs normal tasks. The other is special — it activates the city’s more than 500 air-raid sirens. That mouse is switched off after each use, to prevent accidental clicks.
A radar map used by the specialist has a blue circle drawn around the city. A drone entering the circle can reach the city in about seven or eight minutes, so when one crosses, the specialist immediately activates the sirens.
Much of the job involves waiting, patiently, to see if drones or glide bombs enter the threat perimeter. They can change course or skirt the city on their way to other targets. Specialists are mindful not to activate the alarms too early, for fear of upsetting residents and losing credibility.
There is no waiting, though, when it comes to ballistic missiles. Sirens are activated as soon as a launch is detected.
Threats can be spotted multiple ways. Sometimes, the team itself sees a threat on the radar. The situation center is also in direct communication with the military.
The benefit of that was on display one recent night. A military contact warned of a ballistic missile threat, and the city’s sirens were activated. A warning from the regional administration did not come until three minutes later.
Switching on the alarms involves two steps: flipping a toggle button to trigger the air-alert phone app used by most Ukrainians, and then pushing a big red button on the screen to set off the citywide sirens. It all happens in less than two seconds.
The job requires steady hands, composure and focus, said Alina Ustiuhova, a supervisor. It took six months to fill a chief specialist role, she added.
Dmytro, who has been in the role for three months, said that he had always had a calm demeanor, and that he had grown accustomed to the stress. He sits almost perfectly still during his shift, one palm flat on his thigh.
He refuses to tell his family about the critical role he plays in what many Ukrainians assume is an automated process.
“I don’t want them to know that I have this much responsibility,” he explained. “The less they know, the better they sleep.”
Only his girlfriend knows that he switches on the air-raid alarms, Dmytro said. When she hears the sirens, he said, “maybe she thinks of me each time.”
The post The Secret of How Ukraine’s Lifesaving Air-Raid Alarms Work appeared first on New York Times.
