SYDNEY, Jan. 25 (Xinhua) -- Four men were arrested in Sydney on Thursday in relation to a 54-million-U.S.-dollar shipment of heroin which arrived in the country earlier in the year.

The shipment arrived at Sydney airport from Malaysia and was seized by Australian Border Force (ABF) personnel who noticed anomalies in wooden crates containing wooden handicraft items.

The haul consisted of 400 blocks of heroin weighing 154 kg.

"It's significant, it's the largest in Australia for probably around 10 years for heroin," ABF superintendent Garry Low said.

"This detection makes up over 80 percent of last year's total detections at the border."

Aged between 23 and 31 years old, the arrested men are all foreign nationals and are expected to be formally charged with the crime on Friday.

"We will allege in the investigation that people travelled to our country to distribute a large quantity of drugs," Acting Assistant Commissioner Stuart Smith told local media

"We will allege they were in the act of breaking that down and distributing it into the Sydney market."

During raids across the city on Thursday, police also uncovered 35 kg of methamphetamine.

"Basically, over 75 million U.S. dollars worth of drugs that would have hit the streets," Smith said.