Fox News Media CEO Suzanne Scott announced the tragic news in a note to colleagues. She said Zakrzewski, 55, and Hall were reporting in the village of Horenka when "their vehicle was struck by incoming fire."

Ukrainian officials said Oleksandra Kuvshynova, a producer working with the Fox News team, was also killed in the attack.

Read Scott's note below, which includes comments from Fox News president Jay Wallace.

Dear colleagues,

It is with great sadness and a heavy heart that we share the news this morning regarding our beloved cameraman Pierre Zakrzewski. Pierre was killed in Horenka, outside of Kyiv, Ukraine. Pierre was with Benjamin Hall yesterday newsgathering when their vehicle was struck by incoming fire.

Pierre was a war zone photographer who covered nearly every international story for FOX News from Iraq to Afghanistan to Syria during his long tenure with us. His passion and talent as a journalist were unmatched. Based in London, Pierre had been working in Ukraine since February. His talents were vast and there wasn't a role that he didn't jump in to help with in the field – from photographer to engineer to editor to producer – and he did it all under immense pressure among journalists at every media outlet. He was wildly popular – everyone in the media industry who has covered a foreign story knew and respected Pierre.

Last year, he played a key role in getting our Afghan freelance associates and their families out of the country after the U.S. withdrawal. In December at our annual employee Spotlight Awards, Pierre was given the "Unsung Hero" award in recognition of his invaluable work.