A child was among at least 16 people killed when a Russian missile crashed into a market in the heart of a Ukrainian city, officials in the country said Wednesday, hours after Secretary of State Antony Blinken arrived in the capital Kyiv in a show of U.S. support. 

Calling it a “terrible terrorist act by Russia,” Ukrainian Prime Minister Denys Shmyhal said in a Telegram post that “16 people are already known to have died, including 1 child,” in Kostiantynivka, an industrial city in the eastern Donetsk region. “My sincere condolences to the families and loved ones,” he added. 

Twenty eight people were injured in the strike, Interior Minister Ihor Klymenko said in a separate post on his Telegram channel. He added that a rescuer was among the victims.  

The attack came as Blinken was on a trip to the country in a gesture of support as its three-month-old counteroffensive against Russian forces grinds on.

Blinken, the first top U.S. official to visit Kyiv since the counteroffensive began in early June met with Ukraine’s Foreign Minister Dmytro Kuleba.   

“We want to make sure that Ukraine has what it needs, not only to succeed in the counteroffensive, but has what it needs for the long term, to make sure that it has a strong deterrent,” Blinken told a news conference ahead of the meeting.

This is a breaking news story. Please check back for updates.