A Hong Kong man picked out by an alert Customs officer at Bangkok's Don Muang airport was carrying 17 kilograms of gift-wrapped heroin. Thai narcotics agents said the biggest seizure this year came after Tony Wong Tak-kuen, 26, was spotted behaving oddly at the boarding gate before the departure of the 7 pm Thai Airways International flight to Hong Kong on Saturday. 'His body-language was all wrong,' an airport police officer said. 'He seemed to have a strange relationship with his bag.' When Wong's carry-on bag was opened, Customs officers found 24 gift-wrapped parcels of what turned out to be heroin. The narcotics were worth about HK$4 million in Thailand, but would be many times that amount when sold abroad. The police said Wong claimed not to know what was in the packages which he said he had agreed to carry to Hong Kong for a stranger. 'We were told he did not say much on Saturday. I heard he said 'It's not good. It's not good',' a police officer said. The man's travel documents indicated he had gone to Thailand for short trips in June and September. He returned to the city last Tuesday. China regularly executes the couriers it catches so the Thai route may remain preferable for many. Thailand officially imposes the death penalty for drug trafficking, but the sentence has never been carried out. Western narcotics agents said as much as half the heroin exported from the so-called Golden Triangle, in northeast Burma is still transported through Thailand. Wong's address and occupation were not supplied.