The Asian Football Confederation (AFC) will take over investigations involving the unruly behaviour of Malaysian fans at the AFF Suzuki Cup semi-final first-leg match in the Shah Alam Stadium on Dec 7.

The case was previously investigated by the cup's organiser, Asean Football Federation (AFF).

A group of Malaysian supporters had behaved like hooligans, injuring a few Vietnam supoprters after the match ended with Malaysia losing 1-2 to Vietnam.

AFF secretary-general Datuk Azzuddin Ahmad said he was informed by the AFC that they would be taking over the case, and FAM was required to send them a showcause letter by Monday.

"We cannot interfere anymore, seeing that the AFC has a much higher authority as it represents 46 Asian countries, even though the AFF had sent a showcause letter to FAM on Dec 9," he told reporters here on Saturday.

Azzuddin said he had informed FAM on the matter.

He said based on his experience, FAM would likely face a fine over the incident.

"I don't think AFC will impose a heavier punishment that would see Malaysia forced to play in an empty stadium with no supporters during the second-leg of the AFF Suzuki Cup final at the Bukit Jalil National Stadium on Dec 20.

"It is not as serious if compared to other cases with much more violence," said Azzuddin.

The unruly behaviour of a few Malaysian supporters had received severe criticism from several quarters, including from Youth and Sports Minister Khairy Jamaluddin who has apologised to Vietnam's supporters.