Hong Kong has seized nearly two tonnes of elephant ivory worth about $1.7 million hidden in a shipment from Malaysia and detained a local man over the haul, customs authorities said Wednesday.

Part of a shipment of 794 ivory tusks seized by the Hong Kong\'s Customs and Excise Department inside a container shipped to Hong Kong.

Inspectors found 794 pieces of tusks, weighing 1,898 kilos (4,184 pounds), concealed behind stones in a container marked for factory use at the city\'s port on Monday, a spokeswoman for the customs department told AFP.

A 66-year-old Hong Kong man was arrested and was under investigation, she added, but declined to confirm whether the shipment was destined for China, a major market where ivory is ground up and used in traditional medicine.

If convicted, the man faces a fine and imprisonment of up to seven years under customs or wildlife protection laws.

Anti-trafficking wildlife groups lauded authorities for the haul, part of the illegal elephant ivory trade that has been rising globally since 2004, largely due to increasing Chinese demand.

"This looks like another huge consignment of ivory aimed at the Chinese market," Tom Milliken, a coordinator of wildlife trade monitoring network TRAFFIC, said in a statement.

"The authorities in Hong Kong are to be congratulated on this important seizure, but it is now vital to ensure that all leads are followed to track down those responsible along the entire smuggling chain."

International trade in ivory was banned in 1989 after the population of elephants dropped from the millions in the mid-20th century to some 600,000 by the end of the 1980s.

But seizures have escalated dramatically in the last seven years, driven by Chinese consumption, which is exacerbating Africa\'s elephant poaching crisis, activists say.

In September last year Hong Kong customs seized 384 ivory tusks worth $1.4 million from two containers marked "dried anchovies" in a vessel traveling from Tanzania to the southern Chinese city.

Milliken meanwhile urged Malaysia to step up law enforcement against smuggling, saying the Southeast Asian nation was increasingly used as a transit country for African ivory.

"This latest Hong Kong seizure further underscores Malaysia\'s role as an intermediary country in the illicit flow of African ivory to Asia," he said.

"It\'s time for Malaysia to get tough on international ivory smugglers, who are tarnishing the country\'s reputation."

Malaysian wildlife authorities said last week they were "highly concerned" after police in Tanzania\'s Zanzibar archipelago seized more than 1,000 elephant tusks, which were being smuggled en route to Malaysia.