Shares plunged again yesterday on both national stock exchanges following mounting pessimism from investors, driven by rumours on the market.

According to Vu Bang, chairman of the State Securities Commission, the stock market was negatively affected by inaccurate information, particularly the false rumour related to the arrest of chairman of Masan Group Nguyen Dang Quang.

"Completely inaccurate rumours have driven investors to sell off shares en masse," Bang said, adding the commission had never considered to suspend or shut down the market as this could negatively impact the market sentiment.

Market insiders also warn investors of the phenomenon of speculation or short sales and advised investors to keep calm to avoid falling prey to false rumours of profiteers.

The VN-Index on the HCM City Stock Exchange failed to rebound in the afternoon session, losing 0.11 per cent to 385.78 points while the trading value was down 17 per cent from Monday's level, totalling VND538.5 billion (US$25.6 million).

Some blue chips recovered in the afternoon. Military Bank (MBB), steelmaker Hoa Phat Group (HPG) and Vinamilk (VNM) increased from 1-2.6 per cent.

However, large-caps shares including insurer Bao Viet Holdings (BVH), property developer Hoang Anh Gia Lai (HAG), Eximbank (EIB) and PetroVietnam Finance (PVF) continued to close yesterday at floor prices.

The VN30, which tracks the top 30 shares, was off 0.19 per cent to 454.10.

Financial conglomerate Ocean Group (OGC) was the most active code with 1.9 million shares traded, closing off 4.6 per cent at VND10,400 ($0.50) a share.

On the Ha Noi Stock Exchange, the HNX-Index gave up another 0.96 per cent to end yesterday at 59.73 points on total turnover VND279.2 billion ($13.3 million), down 13 per cent from Monday.

Blue chips on the northern bourse performed better, with the HNX30 – representing the exchange's top 30 shares – rose 0.36 per cent to 112.34 points.

VNDirect Securities (VND) became the most active code with almost 4.8 million shares changing hands, rising 2.1 per cent to end yesterday at VND9,600 ($0.45) a share.

According to Nguyen Duy Hung, chairman of Saigon Securities Inc (SSI), after dropping for several sessions in a row, prices of many stocks have become more attractive. He predicted that with lower interest rates and more controlled inflation, the stock market would get better in the medium- and long-term.

Foreign investors suspended trading on the HCM City exchange but continued to be net buyers on the Ha Noi bourse, picking up shares worth VND8.6 billion ($410,000) worth of shares.