The investigation had begun after a complaint was lodged by Indonesian state-controlled steel maker PT Krakatau Steel, Bachrul Chairi, head of the Trade Ministry's security committee, told Reuters on Friday. Indonesian business groups last year urged the government to hike tariffs on Chinese steel to rein in cheap imports, after Krakatau said it has to restructure and lay off 30% of its workers through 2020.

"(The) Indonesian Trade Security Committee has been conducting an anti-dumping investigation which began on March 9 on imports of hot rolled coil of other alloy steel products originating from China," Chairi said. Indonesia's top steel producer had put forward enough evidence for the committee to initiate an investigation, including allegations that the company is suffering losses due to imports of the product from China, he added.

(Reporting by Bernadette Christina Munthe; Writing by Fransiska Nangoy; Editing by Alexander Smith)