PERTH, Sept. 25 -- Nyrstar NV's Port Pirie silver- processing plant was affected by a fire today that was caused by a nitric-acid spill, Adelaidenow.com reported, without saying where it got the information.

The blaze at the smelter, which broke out 3:50 p.m. local time, was put out after an hour, the news service reported. Workers escaped injury, the report said.

An after office-hours telephone call by Bloomberg News to Nyrstar's Port Pirie office wasn't answered.

Port Pirie, which has a smelter and refinery, produces lead, silver, zinc, copper and gold, according to the company's website. The site, about 200 kilometers (127 miles) north of Adelaide in South Australia state, can produce about 235,000 metric tons of refined lead and lead alloys, 16 million ounces of refined silver and about 45,000 tons of zinc, it said.