Ukrainian President Volodymyr Zelenskyy announced Wednesday the Security Service of Ukraine and the police arrested a suspect who they say coordinated with Russian forces in Tuesday's missile attack on Kramatorsk, a city in the Donetsk region.

The missiles struck a popular pizzeria and killed 12 people, including three children. More than 60 people were injured, the president said in a public address.

The unidentified "spotter" was charged with treason, according to Zelenskyy.

"Anyone in the world who does not understand that one cannot be an accomplice of a terrorist state must be held accountable by the entire international community," he said.

-ABC News' Will Gretsky

A senior U.S. official tells ABC News that Yevgeny Prigozhin thought he would have help from the Russian military.

Both former Russian military officers and some others in Moscow had conversations with Prigozhin before he started his march, the official said.

The U.S. doesn't believe Russian President Vladimir Putin realized this beforehand, and the officers sided with Putin in the end, the official said.

According to the official, Prigozhin was shocked he didn’t have support.

-ABC News' Martha Raddatz

Two Russian missiles struck Kramatorsk, a city in Ukraine's Donetsk region, killing at least four people, according to officials.

At least 47 people were injured in the attack, but the death and injury toll could rise.

One of the deceased victims was a 15-year-old and one of the wounded victims was a child under a year-old, officials said.

One missile struck an eatery downtown and the other one hit the outskirts of the city, Andriy Yermak the head of the Ukrainian Presidential Office said.

A restaurant and a hotel were badly damaged as a result of the strikes, according to officials.

Crews continued to dig through the rubble to search for victims throughout the evening.

"Each such manifestation of terror proves over and over again to us and to the whole world that Russia deserves only one thing as a result of everything it has done - defeat and a tribunal, fair and legal trials against all Russian murderers and terrorists," Ukrainian President Volodymyr Zelenskyy said in a statement.

-ABC News' Fidel Pavlenko and Ellie Kaufman

The U.S. announced additional sanctions targeting the Wagner Group, specifically going after gold companies and a Russian man it says are illicitly funding the Wagner Group’s operations in Ukraine and Africa.

Central African Republic based companies Midas Resources SARLU and Diamville SAU, Dubai based company Industrial Resources General Trading and Russia based company Limited Liability Company, re connected to Wagner’s leader Yevgeny Prigozhin, who is already subject to U.S. sanctions along with numerous other entities linked to the Wagner Group, according to the Department of the Treasury’s Office of Foreign Assets Control.

Andrey Nikolayevich Ivanov, a Russian national, and an executive in the Wagner Group, allegedly worked closely with Prigozhin’s entity Africa Politology and senior Malian government officials on weapons deals, mining concerns, and other Wagner Group activities in Mali, OFAC said.

"The Wagner Group funds its brutal operations in part by exploiting natural resources in countries like the Central African Republic and Mali," Brian Nelson, the U.S. under secretary of the treasury for terrorism and financial intelligence, said in a written statement. "The United States will continue to target the Wagner Group’s revenue streams to degrade its expansion and violence in Africa, Ukraine, and anywhere else."

-ABC News' Ben Gittleson

Ukrainian troops have reportedly seized a small village on the Russian-occupied eastern bank of Dneipr after crossing the river from the liberated city of Kherson, according to Russian accounts on Tuesday.

A small Ukrainian force has managed to dig in to the village of Dachi after making a landing there a few days ago and are trying to expand the beachhead. Ukrainian troops in small boats crossed the river and landed at the base of the ruined Antonivskiy Bridge, which they destroyed last year.

Russian military bloggers reported very heavy fighting on Tuesday, saying Russian airborne units have been trying unsuccessfully to dislodge the Ukrainians for the past four days. Russian aviation and heavy artillery have been firing on the Ukrainian position.

So far, the Russian side claims some 70 Ukrainian soldiers are dug in, covered by intense artillery fire from across the river. The Russian accounts say Ukraine is trying to move reinforcements across. Video released by Ukraine also shows a Russian APC being destroyed in the village of Oleshkjy, further south, indicating the bank south of Kherson is now contested.

Ukrainian troops have also managed to advance and liberate Rivnopil, a village on the Zaporozhzhia front, breaking through after more than two weeks of fighting. It's notable because the Russians had been fighting hard to hold it.

Taken together the advance there, the landing in Kherson and advances near Bakhmut are small signs the Ukrainian counteroffensive may be starting to pick up steam and the Russians are coming under growing pressure.

-ABC News' Patrick Reevell