Investor watchdog Securities Investors Association (Singapore) wants action taken against three troubled listed foreign firms and for investors to be updated on the process.

Sias founder David Gerald said in a statement yesterday that shareholders have been frustrated with the shares suspended from trading. He called on the authorities in Singapore and overseas to investigate alleged claims and help settle issues facing the companies so audits can be completed and trading resumed.

He named S-chips (Singapore-listed Chinese firms) China Fibretech, China Sky and China Environment, adding that alleged unethical conduct by some in those companies has caused losses to shareholders.

Customers of China Fibretech had claimed 466 million yuan (S$95.7 million) in damages and losses. The firm said it would investigate and won't agree to any liability or compensation before the board's approval. But, Mr Gerald noted, China Fibretech chief executive Wu Xinhua and his uncle approved payment, claiming they did this to avoid further compensation.

Mr Gerald also raised concerns over management and financial controls at China Environment and one of its units. And China Sky has been suspended from trading since Aug 12. This comes after a four-year suspension involving suspected regulatory breaches was lifted in September 2015.

Mr Gerald called on the authorities to investigate: "It would be comforting for these shareholders, in dire straits, to receive updates from time to time."