A spokesperson for the local fire and rescue service told Reuters earlier it was crude oil that was on fire. She said there were no buildings on fire, and there did not appear to be risk of the flames spreading.
The Nynas AB spokesperson said six persons had been treated onsite after inhaling smoke, one of which had been taken to hospital for further treatment while the others had returned to work.
Images published by daily Aftonbladet and public broadcaster Sveriges Radio showed thick black smoke rising over the refinery located some 50 kilometres (30 miles) south of the Swedish capital Stockholm. (Reporting by Anna Ringstrom, Simon Johnson and Essi Lehto, editing by Terje Solsvik and Louise Heavens)
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