At least one person was killed and five were injured in an explosion that occurred at Romania's Black Sea crude oil refinery Petromidia on July 2, authorities said.
The cause of the blast has yet to be determined, officials said.
The refinery is owned by Rompetrol Rafinare, part of Kazakhstan's KazMunayGas (KMG) International Group.
Rescue teams and firemen are working to isolate and put down the fire, said Silviu Cosa, the prefect of Constanta county where Petromidia is located, adding that the fire poses no risk of causing further blasts.
Prime Minister Florin Citu wrote on his Facebook page that he has instructed government officials to assess whether the evacuation of locals and tourists is needed.
Built during communism, Romania's largest refinery is located just several kilometers north of the Black Sea port of Constanta and in the immediate vicinity of Mamaia, the country's largest sea resort.
Environment Minister Barna Tancos told the media that while the explosion does not pose an immediate danger due to the direction of the wind, which carried the black smoke away toward the sea, the risk of a major environmental accident is still high.
In 2019, KMG said that it had invested some $1 billion in the modernization of Petromidia and in the increase of its refining capacity from 3.5 million to over 5 million tons of crude annually.