* Blumont, LionGold, Asiasons lost $6.35 billion market value in October
* Authorities investigating possible breach of securities act
* Police contact Blumont, LionGold; Asiasons says no order from police (Adds comment from source, Asiasons, Innopac)
By Anshuman Daga and Rachel Armstrong
SINGAPORE April 3 (Reuters) - Singapore's police force and central bank are looking into suspected trading irregularities in three companies at the centre of last year's penny-stock crash that led to a sharp fall in trading volume in the city-state's equity market.
Share prices in Blumont Group Ltd, LionGold Corp Ltd and Asiasons Ltd plunged last October, wiping out around S$8 billion ($6.35 billion) in market value in just two days after huge run-ups. The scandal led to a series of proposed reforms to the city-state's stock trading rules.
Late on Wednesday, the central bank said it is working with white collar crime police unit the Commercial Affairs Department (CAD) on possible breaches of the Securities and Futures Act related to trading in those three stocks on Singapore Exchange Ltd (SGX).
"What you are seeing is the second stage of the investigation after the initial review by SGX," said one person with knowledge of the matter. "Since the SGX has no power to enforce any possible criminal wrongdoing, they have to turn to the CAD in the next phase of this saga."
Blumont said on Wednesday that its subsidiary, G1 Investments, had been contacted by the CAD and been asked for all corporate electronic data from January 2011 relating to its executive chairman, Neo Kim Hock, and executive director James Hong.
Blumont, which mainly invests in mining assets, said the investigation is in relation to an offence under the Securities and Futures Act, without giving any further details.
In a statement on Thursday, Asiasons said neither the company or its subsidiaries nor any of its directors and officers have received any notice or order from any governmental authorities to assist in the investigation.
LionGold said on Wednesday that its subsidiary, LionGold Investments Pte Ltd, and the company has been informed by the CAD of a similar investigation.
Shares of LionGold, Blumont and Asiasons declined between 2 and 15 percent on Thursday.
Blumont's chairman-designate, Alexander Molyneux, said the company was not able to comment further on the matter.
Another Singapore company, Magnus Energy Group Ltd , said two of its subsidiaries and one former subsidiary have also been asked to help the CAD with investigations. Magnus Energy is a shareholder in LionGold, according to Thomson Reuters data.
Three other stocks linked via shareholdings or directors to the three companies at the centre of the scandal have also asked for their shares to be suspended.
Trading in ISR Capital, IPCO International Ltd and Annica Holdings, has been halted pending announcements.
Singapore has emerged as one of Asia's leading financial centres, but its stock market has struggled recently with a drop in trading volumes and "ultra penny stocks", which trade for as little at S$0.001 and are the most actively traded shares. ($1 = 1.2591 Singapore dollars) (Additional reporting by Andrew Toh; Editing by Christopher Cushing and Ryan Woo)