SARAJEVO, Bosnia-Herzegovina — Police say an explosion at a Russian-owned oil refinery in northern Bosnia has killed one worker and injured nine.

The blast rocked the neighborhood around the refinery in Bosanski Brod late Tuesday and was heard on the other side of the border, across the Sava river in Croatia. Firefighters extinguished a huge fire early Wednesday.

Dr. Milivojko Zubic, who was on the night shift in the urgent care center in Bosanski Brod, said staff treated nine patients, of whom six were taken to the hospital in the nearby city of Doboj.

The plant is majority-owned by Russian state-owned oil company Zarubezhneft and has the capacity to process 1.2 million tons of petroleum per year.

Authorities say the cause of the blast is being investigated.

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