HONG KONG (AFP) - Fifa has launched an official investigation over the behaviour of Hong Kong fans in a match against Qatar after they jeered the Chinese national anthem and threw a drink at a rival player.

Fans booed the "March of the Volunteers" - the anthem they share with China - at a World Cup qualifier played in Hong Kong last week which the home side lost 2-3.

Last year's "Umbrella Movement" mass pro-democracy protests have soured attitudes in the semi-autonomous territory towards Chinese authorities and prompted resentment among some fans that the Chinese anthem is used to represent the city's team.

The Hong Kong Football Association (HKFA) said on Friday that Fifa, world football's governing body, was also investigating an incident where a carton of lemon tea was thrown at a Qatari player.

"The HKFA has received correspondence from Fifa (dated Sept 15) announcing that disciplinary proceedings have been opened against the HKFA in relation to incidents that took place during the recent Hong Kong v Qatar match," the HKFA said in a statement.

Fifa said the incidents were a violation of its regulations, according to the statement.

"It is regrettable that, despite continuous pleas for fans to behave themselves, it appears that the behaviour of a small minority of fans has placed the HKFA in this potentially damaging situation," it added.

HKFA said it had been asked to submit information to Fifa by Sept 22.