A blast at a petroleum storage facility in the Netherlands' Rotterdam port killed one person and injured six others on Thursday, with authorities investigating the cause of the explosion.The blast occurred at around 11.30 am local time during maintenance work on a storage tank operated by energy commodities trader Gunvor. A company spokesperson described it as an “incident” and said Gunvor was cooperating with authorities.

Police said there was no immediate indication of sabotage, but all possible causes were being considered.The explosion took place at the Port of Rotterdam, Europe's largest port and a major centre for oil and fuel imports and storage.

The sprawling facility also houses major refineries operated by Shell, BP, ExxonMobil and Vitol.Shell said its operations were unaffected, while the port said its LNG terminals were not hit by the blast. Gas flows at Rotterdam's Gate LNG terminal briefly dipped before becoming volatile, although it was unclear whether that was linked to the explosion or a separate power outage elsewhere in the port.ExxonMobil said a power outage affecting its 191,000-barrel-per-day refinery had been resolved and that operations were normal.

Rotterdam Port and local authorities said the outage was unrelated to the blast.The incident is being closely watched because the port is a major energy hub for northwestern Europe. The Gate terminal is one of the region's key LNG import facilities, while Dutch gas storage levels are currently around 40% ahead of the winter heating season.