Embattled water treatment firm Hyflux, which is in the midst of securing a rescue deal, has been dealt another blow.

The authorities have launched a criminal investigation into the Singapore company and some of its directors for suspected false and misleading statements, as well as non-compliance with accounting standards.

The investigation by the police's Commercial Affairs Department, the Monetary Authority of Singapore and the Accounting and Corporate Regulatory Authority will ascertain if there were lapses in the company's disclosures concerning the Tuaspring Integrated Water and Power Project. Other accounting lapses between 2011 and 2018 are also being looked at.

Among the directors under investigation is Hyflux's executive chairman Olivia Lum, who was the company's only executive director during that period.

This is the latest twist in Hyflux's protracted struggle to regain its footing since May 2018, when it sought court protection for debt restructuring.

The Tuaspring project had cost Hyflux $1.05 billion. But national water agency PUB took over the desalination plant last year "to safeguard Singapore's water security".

The criminal probe is separate from Hyflux's ongoing corporate rescue process, said the authorities.

Yesterday, potential white knights Aqua Munda and Utico reiterated their interest in Hyflux.