A Russian military unit killed dozens in Bucha, a Times investigation shows.

When videos and photos emerged in April showing bodies of dozens of civilians strewn along a street in Bucha, Ukrainians and the rest of the world voiced horror and outrage. But in Russia, officials had a completely different reaction: denial.

President Vladimir V. Putin dismissed the gruesome scene as “a provocation,” and claimed that the Russian Army had nothing to do with it.

But an eight-month visual investigation by The New York Times concluded that the perpetrators of the massacre along Yablunska Street were Russian paratroopers from the 234th Air Assault Regiment led by Lt. Col. Artyom Gorodilov.

The evidence shows that the killings were part of a deliberate and systematic effort to ruthlessly secure a route to the capital, Kyiv. Soldiers interrogated and executed unarmed men of fighting age, and killed people who unwittingly crossed their paths — whether it was children fleeing with their families, locals hoping to find groceries or people simply trying to get back home on their bicycles.