A bitter war of words between Hong Kongers and mainland Chinese heated up Thursday as southern city residents sought funds to insult their neighbours as "locusts" in a front-page newspaper ad.

Online group Golden Forum is asking users to donate money for an advert in one of the southern city's most widely-read newspapers portraying mainlanders as locusts, an insult used by Hong Kongers against northerners.

The "Anti-Locusts" campaign -- which local media reported had already raised more than HK$40,000 ($5,200) -- comes in response to remarks by a Chinese professor calling Hong Kong people "bastards", "dogs" and "cheats".

Kong Qingdong said Hong Kong people were "used to being the dogs of British colonialists -- they are dogs, not humans".

The professor was hitting back after an online video went viral showing Hong Kongers scolding a mainland girl for flouting rules against eating on the city's subway trains.

That incident followed a music video made in Hong Kong last year that sneered at mainlanders as "locusts who shout in restaurants, hotels and stores", and show scant regard for the citys rules and social conventions.

The tensions have been fuelled by Hong Kongers' concerns about Beijing's shadowy political influence in the semi-autonomous former British colony, which was returned to Chinese rule in 1997.

More mainland Chinese tourists and investors are visiting Hong Kong than ever before, changing the city's retail and property markets, often to the disadvantage of locals.

Mainland women flock to Hong Kong to give birth in the city's well-appointed hospitals, raising delivery costs and crowding local women out of maternity wards.

Last week Italian clothing chain Dolce & Gabbana apologised to the people of Hong Kong for allegedly discriminating against them in favour of wealthy mainland shoppers.

A recent survey found more Hong Kong people identified themselves as Hong Kongers instead of Chinese than at any time since the handover.