Prime Minister Viktor Orbán said Thursday that last week’s inferno at a Hungarian oil refinery could have been caused by an “external attack,” adding an investigation was still ongoing. 

A blaze broke out last Monday night at the Danube Refinery in Százhalombatta, south of the capital Budapest. The refinery, operated by Hungarian energy company MOL, is the country’s largest and primarily processes crude oil from Russia. 

“The investigation is in full swing,” Orbán wrote on social media. “We do not yet know whether it was an accident, a malfunction, or an external attack.” 

His public musing about possible sabotage contradicts MOL, which last week said there was no evidence of an attack.  

“The Polish foreign minister advised the Ukrainians to blow up the Druzhba oil pipeline,” Orbán added. “Let’s hope it’s not that kind of case.” 

He was apparently referring to Polish Foreign Minister Radosław Sikorski’s remarks on social media last week that he hoped Kyiv “finally succeeds in knocking out” the strategically important pipeline, which feeds Russian oil into Hungary. 

Budapest has come under criticism from Ukraine and its allies for continuing to import Russian oil throughout Moscow’s war, even as the rest of the EU has largely weaned off the Kremlin’s energy. 

The Hungarian leader has argued that Budapest has no choice but to rely on Russia for cheap oil and gas due to its landlocked geography, insisting prices would explode for consumers otherwise and even vowing to circumvent U.S. sanctions on Russian oil companies. That’s despite neighboring Croatia’s insistence that it could meet Budapest’s energy needs with its own pipeline.

Orbán added Thursday he had instructed his government to inform MOL that it shouldn’t raise energy prices for consumers in response to the fire at the refinery.