Johannesburg - Two Chinese nationals were removed from an Istanbul-bound plane just before take-off at OR Tambo International Airport on Sunday.This was after SARS customs officials discovered 10 rhino horns in their luggage. Both passengers were arrested by the police and remain in custody.Sunday's bust was the third time that Chinese nationals have been arrested for rhino horn trafficking in less than three days. The common thread in all three cases was that Hong Kong was the destination.The seizure at OR Tambo yielded approximately 24.96kg of horn, which was valued at nearly R5m, SARS spokesperson Sandile Memela said.The discovery was made when customs officials followed up on intelligence information about a suspicious bag on an airliner bound for Istanbul, Turkey. After intercepting the first bag, further information led them to a second item of baggage in the hold, which was also off loaded for closer inspection"After both bags had been removed from the cargo hold of the airliner, their contents were scanned and inspected. Four full-sized rhino horns were found in the one bag, while the other bag was found to contain six horns," Memela said."The two passengers, their bags, plus the contraband were handed over to the South African Police Service for further investigation," he said.Memela declined to answer questions that he said "are sensitive to our investigations"."SARS is not working alone, but collaborating with other agencies on the ground," he added.In two separate rhino horn trafficking incidents, Hong Kong customs agents intercepted two male passengers at Hong Kong International Airport on Friday and Saturday.In Friday’s case, the passenger had flown from OR Tambo with 2.5kg of suspected rhino horn wrapped in tin foil in his check-in luggage, while the second passenger arrived on Saturday via Jakarta, Indonesia, with 10.5kg of suspected rhino horn.