He described Leung Pui, 54, as the "planner and organiser" of the crime. Leung had been released from jail just five months before the attempted robbery in September last year. He received the toughest jail sentence of nine years and four months.

The four mainland men - Cheung Hiu-wai, 36, Ho Bin, 38, Lo Siu-wah, 37, and Shing Cheung, 36 - and two Hong Kong men - Wong Wai-keung, 53, and Chau Cheung-lun, 50 - were jailed for terms of eight years and four months to nine years.

The seven men all pleaded guilty to a joint charge of attempted robbery relating to their ambush of a couple in Hung Hom on September 13 last year.

Prosecutor Lenny Cheng told the court that police had learned the Leader Realty Money Exchange Shop in San Po Kong had been targeted by robbers in July last year. Police began surveillance of the shop later that month. Between September 9 and 11, the seven defendants were seen near the shop and outside the Hung Hom home of the couple who own it.

On the night of the incident, the couple left their shop to head home, carrying a rucksack containing HK$341,500 in cash.

The gang followed them to Hung Hom, and the four mainlanders ambushed the couple, wielding knives and trying to snatch the rucksack.

Police arrived on the scene but the men fought back. One officer had his leg slashed in the struggle.

The court heard that Leung had been released from prison in April last year. He approached Wong to act as a lookout and the others were recruited later.

Ho claimed that he thought he had been hired as a debt collector, not to commit a robbery.