Russia fired cruise missiles Thursday at a western Ukraine city far from the front line of the war, killing at least four people in an apartment building in what officials said was the heaviest attack on civilian areas of Lviv since the Kremlin’s forces invaded the country last year.

The nighttime attack destroyed the roof and the top two floors of a residential building, injuring 34 people. Emergency crews with search dogs went through the rubble.

The youngest victim was 21 years old and the oldest was 95, according to Maksym Kozytskyi, head of Regional Military Administration.

“This woman survived the Second World War but, unfortunately, she didn’t survive” Russia’s full-scale invasion of Ukraine, Kozytskyi said.

Debris and wrecked parked cars lined the street outside the building, which overlooks a small neighborhood park with swings and climbing frames amid trees.

Lviv Mayor Andriy Sadovyi said around 60 apartments and 50 cars in the area of strike were damaged. He announced two days of official mourning.

U.S. Ambassador to Ukraine Bridget Brink described the attack as “vicious.”

“Russia’s repeated attacks on civilians are absolutely horrifying,” she tweeted.

Ukraine’s air force reported it intercepted seven of the 10 Kalibr cruise missiles that Russia fired from Black Sea toward the Lviv region and its namesake city — more than 500 miles away — around 1 a.m. Thursday.

The Kremlin’s forces have repeatedly hit civilian areas during the war, though Russian officials say they choose only targets of military value.

City is Near Poland Border

Lviv is near the western border with Poland and is more than 300 miles from the front lines of the war in eastern and southern Ukraine, where Kyiv’s counteroffensive to dislodge Russian forces is in its early stages.

Sadovyi, the mayor, addressed residents in a video message, saying the attack was the largest on Lviv’s civilian infrastructure since the beginning of last year’s invasion.

“Russians are hitting us. That’s how they love us. I’m sorry for those people who were killed. They were young. So sorry for them,” said Ganna Fedorenko, a local resident, holding her hands crossed on her chest. She received injuries on her face, and an adhesive plaster turned red with blood on her right cheek. “This is terrible. They hit civilians.”

The Ministry of Internal Affairs said 64 people had to leave their homes.

Ukrainian President Volodymyr Zelenskyy promised “a response to the enemy. A tangible one.”

He went later Thursday on an official trip to Bulgaria at the invitation of its new pro-Western government, with talks about weapon supplies on the agenda.

Ukrainian air force updates about the missiles’ course during the night showed they flew to the Kyiv region first, then turned west toward Lviv. Russia often changes the route of their missiles and drones to find weak spots in Ukraine’s air defenses.

In the early days of the war, Lviv served as a main transit point for millions of refugees from different parts of the country that crossed the border to Europe. Hundreds of thousands of Ukrainians from the east and south remained in the calmer and safer Lviv.

Like the rest of the country, Lviv suffered power outages when Russia fired hundreds missiles over the winter, aiming to destroy Ukraine’s energy system. However, the attacks in the city were not as frequent as in the capital Kyiv, and Thursday’s strike was a deep shock for many in the city.

Ukrainians shared messages of support on social media for Lviv residents.