HANOI (AFP) - Vietnam's football authorities will investigate the country's team for suspected foul play after their disastrous 4-2 loss to Malaysia at the AFF Suzuki Cup, an official said on Friday, amid suspicions of match-fixing.

The home team disappointed millions of fans on Thursday night at Hanoi's My Dinh stadium with a chaotic performance that handed Malaysia four first-half goals, including an own goal from Dinh Tien Thanh.

"The Vietnam Football Federation will immediately ask for police to investigate the match," VFF deputy chairman Nguyen Xuan Gu said in a strong indication officials believe team members might have played poorly on purpose.

"We will seriously punish wrongdoing if we find any. The goals we let in were unacceptable, especially as we were playing at our home stadium," Gu added.

Vietnam has endured a series of corruption scandals, both at international tournaments and its local V-league.

Football betting and other forms of gambling are illegal but widespread in communist-ruled Vietnam, and many fans place bets online with networks based inside the country or in Hong Kong, Macau and other cities.

In 2007 two Vietnamese footballers were jailed and six others given suspended sentences over rigging an Under-23 match against Myanmar at the 2005 SEA Games in return for cash from a betting syndicate.

In late November, the Asean Football Federation agreed that the Swiss-based data company Sportradar would monitor all 18 matches at the Suzuki Cup in a move aimed at stamping out potential match-fixing.

"We are determined to clean up Vietnamese football," Gu said on Friday.

Fans in the football-mad nation have expressed dismay at the defeat, which overturned Vietnam's 2-1 aggregate lead from the first leg.

"It was unbelievable. They played as if they were kids. They let all the fans down," said Hanoi businessman Nguyen Van Hung who was at the match.