TIMIKA, Indonesia (Reuters) - A fire broke out at the main port used by copper miner Freeport-McMoRan Inc in Papua, Indonesia, on Thursday night, the company said.

The fire occurred at the Amamapare port in a plant where copper concentrate from the giant Grasberg copper mine is processed before loading onto vessels for shipping.

The fire broke out at 6.30 pm and was extinguished by port rescue workers at around 7 pm, Freeport spokesman Riza Pratama said in a statement. The incident would have no impact on shipments, he said.

The cause of the incident was not immediately clear but maintenance had been carried out at the port earlier on Thursday, company sources said.

“This incident is still being investigated and will be reported to the Energy and Mineral Resources Ministry and Mining Inspector,” Pratama said.