HONG KONG (AFP) - Hong Kong said on Friday it had seized more than a tonne of ivory worth about US$1.4 million (S$1.72 million) in a shipment from Kenya, the city's third big seizure in less than three months.

Customs said they seized the 779 pieces of ivory tusk, weighing 1.3 tonnes, that were cut up and hidden in five wooden boxes along with stone plates in a container marked "architectural stones" on Thursday.

The haul was worth an estimated HK$10.6 million ($1.4 million).

"It is not very often that you see architectural stones from Kenya... (that's why) we saw this container as possibly storing high risk goods," customs official Clare Kwan told reporters.

The department declined to say where the shipment, which passed through Malaysia, was headed for. No arrests have been made so far.

The latest haul comes less than three months after Hong Kong made its record seizure in October of 1,290 pieces of tusk and a small number of ivory ornaments from Kenya and Tanzania that weighed a total of 3.81 tonnes.

In November, customs officers intercepted another container from Tanzania carrying 569 pieces of unpolished tusks weighing about 1.3 tonnes.

Despite the large seizures, customs denied Hong Kong had become a smuggling hub for the illicit ivory trade.

"There is no information suggesting that there is an increasing trend of smuggling ivory tusks detected," ports control head Vincent Wong told the same news conference.

Under Hong Kong law, anyone found guilty of importing unmanifested cargo into the southern Chinese city - a major shipping hub - faces imprisonment of up to seven years and a maximum fine of HK$2 million.

In addition, those guilty of importing, exporting or possessing an endangered species for commercial purposes face up to two years in jail and a maximum HK$5 million fine, customs officials said.

The international trade in elephant ivory, with rare exceptions, has been outlawed since 1989 after elephant populations in Africa dropped from millions in the mid-20th century to some 600,000 by the end of the 1980s.

However, a rise in the illegal trade in ivory has been fuelled by demand in Asia and the Middle East, where elephant tusks are used in traditional medicines and to make ornaments.

Africa is home to an estimated 472,000 elephants whose survival is threatened by poaching, illegal game hunting and habitat loss.