(Reuters) - Prices for aluminium raw material alumina have hit their highest in almost six months after a blaze at the Jamalco refinery in Jamaica led to fears of tighter supply.

COMEX alumina futures, assessed free-on-board (FOB) from key producer Australia, rose to $302.14 per tonne, up from $300.48 a tonne on Friday and the highest since Feb. 25. Alumina prices have been climbing since mid-April amid strong demand for aluminium and disruption in China due to flooding.

Hong Kong-based Noble Group Holdings, which partners the Jamaican government in the Jamalco joint venture, said a “major fire” broke out in the powerhouse that produces power, compressed air and steam for alumina-refining operations on Sunday.

It has since been extinguished, with no serious injuries reported, the company said on Monday, adding that “a full assessment of the damage will be done in the coming days.”

The Jamalco plant can produce up to 1.4 million tonnes per year of alumina, which is refined from bauxite. Global alumina production in 2020 was 134.4 million tonnes, according to the International Aluminium Institute.

“It is expected that market participants will be focused on the possibility of a disruption to production,” Australian investment management firm Shaw and Partners said in a note to clients on Tuesday.