Thousands of workers of PT Freeport Indonesia, the Indonesian unit of US mining giant Freeport-McMoRan operating in Papua, launched a strike on Thursday, planned to last for a month.

They launched the strike at midnight, and started to leave the mining site in Grasberg at about 6.30 a.m. on Thursday.

Freeport Indonesia labor union spokesman Juli Parorongan said at least 37 buses would be used to transport the workers.

“There will be no mass gathering for orations. Gathering people together is not necessary in a strike. The point is we have stopped working,” he added on Thursday in Jayapura, as quoted by kompas.com.  

The strike was launched following a deadlock in negotiations between Freeport Indonesia workers and the company's management, although it is not clear yet what the negotiations are about.

Freeport Indonesia spokesman Ramdani Sirait said the company was optimistic that the negotiations could continue.