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June 27 Indonesian coal miner Asia Resource Minerals Plc (ARMS), which is battling to turn around its business, named Bob Kamandanu as chairman after investors did not re-elect Chris Walton at Friday's annual shareholder meeting.
ARMS's stock tumbled as much as 14 percent, making it the top percentage loser on the London Stock Exchange.
The miner, previously known as Bumi, also said its largest shareholder and former chairman, Samin Tan, had stepped down as a non-executive director.
Tan owned about 24 percent of ARMS as of Dec. 31, according to Thomson Reuters data.
ARMS is going through an overhaul as it tries to improve its performance that has been hit by weaker coal prices and shareholder infighting. Its shares have lost more than 81 percent of their value since the company listed in 2010.
Kamandanu was added to ARMS's board earlier this month as an independent non-executive director, put forward by Tan and financier Nat Rothschild, the company's second-largest shareholder.
Kamandanu, who is also the chairman of the Indonesian Coal Mining Association and CEO and president of Indonesdian coal company PT Delma Mining Corp, has previously held roles at British American Tobacco, Cigna Corp, Chandra Asri and Pirelli.
The company replaced its chief executive, Nick von Schirnding, just over two weeks ago with Amir Sambodo, an independent non-executive director.
ARMS said at the time that the board had made the decision to change the chief executive as it felt the role should move from London, where von Schirnding is based, to Indonesia, near the Berau coal mine, ARMS's sole coal asset.
Shares in ARMS were down 12 percent at 1717 GMT on Friday. (Reporting by Richa Naidu in Bangalore; Editing by Kirti Pandey and Saumyadeb Chakrabarty)