SAO PAULO, Brazil — An early morning fire at Brazil's Santos Port hit warehouses Friday, potentially destroying up to 300,000 tons of sugar.

"Three warehouses were destroyed by the fire and we are trying to control the fire now in a fourth," a representative for the fire department in Santos told Reuters.

The agency that operates the port said four employees suffered minor injuries.

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The blaze started at about 6:15 a.m. local time and caused severe damage to at least four warehouses.

The cause was not immediately known.

Copersucar, the world's largest sugar trader, owns six warehouses at the Santos Port, each with the capacity to hold 50,000 to 100,000 tons. The port, located in São Paulo state, is the world's main source of raw sugar shipments.

According to Bloomberg, ships were scheduled to load shipments at the Santos terminal from yesterday through Nov. 3.

"We are going into the tail end of the Brazilian crush and production there has already been affected by rains," Kona Haque, an analyst at Macquarie Group Ltd. in London, told Bloomberg.

"This is another problem they didn't need and we could lose up to 300,000 tons. Speculators had already started to buy and the bullish news will fuel that short-term bullishness further," she said, referring to sugar prices in the aftermath of the fire.

Fabrienne Pointier at data provider Platts told Reuters the real damage was to Copersucar's infrastructure, not the loss of so many tons of sugar. In June, Copersucar began an expansion project that would double its exports to 10 million tons of sugar a year.