The comments were made by presiding Judge Peter Berman as he heard sentencing submissions for the three Chinese nationals 19-year-old Chen Zhang, 20-year-old Li Ying and 19-year-old Zhau Lin Xing.

The offenders, who are in Australia on student visas, pleaded guilty to kidnapping Philip Chau at knifepoint outside his Chinatown restaurant BBQ King, in July last year.

Chau was held for two-and-a-half days in a unit in Hurstville in Sydney’s southern suburbs, before being released when the ransom was paid.

The court was told Chau was bound, gagged punched, kicked and denied food and water and after he tried to escape.

Chen has apologised for the physical and psychological damage he caused to Chau.

The three men have spent 10 months in protective custody at Silverwater remand centre.

They will be sentenced on 21 May.