Shares pared earlier gains to tumble in both Hanoi and Ho Chi Minh City on October 1.

Although Vietnam's PMI increased from 49.4 to 51.5 in September, the best result since April 2011, investors sold off shares after news was released that the US Government had shut down due to a budget dispute.

The nation's consumer price index could continue to increase by 0.5-0.6 percent this month due to the impact of the rainy season and the increasing prices of several key commodities, according to the Ministry of Industry and Trade's market management team.

On the Ho Chi Minh City Stock Exchange, the VN-Index lost 0.08 percent to close at 492.24 points, while the VN30, tracking the bourse's 30 leading shares in terms of capitalisation and liquidity, edged down 0.35 percent to 549.63 points.

The blue chips were mixed, but losers still overwhelmed gainers. Kinh Do Confectionery (KDC) retreated 2.9 percent, while financial group Ocean (OGC), logistics company Gemadept (GMD), PetroVietnam Drilling Services (PVD) and Vinamilk (VNM) closed down between 1.4-2 percent.

The total trading value rose around 60 percent over the level of September 30 to 1.65 trillion VND (77.8 million USD) with over 102 million shares changing hands.

On the Hanoi Stock Exchange, the HNX-Index shed 0.05 percent to 60.93 points.

Trading value fetched 363.7 billion VND (17.1 million USD) on a volume of 45.4 million shares, increasing around 42 percent over the previous session.

However, the HNX30, composed of the northern bourse's top shares, managed to add 0.01 percent to reach 113.30 points.

While domestic investors sold, foreign investors increased their net buying value by nearly four times to 120.8 billion VND (5.6 million USD).-VNA