Tel Aviv reported on Wednesday that six Israeli citizens have been detained on suspicion of running an international organ-trafficking ring and breaking promises to donors to pay for their removed kidneys.
Police also said that they prevented several would-be donors from giving up their kidneys, intercepting some at Israel's airport as they were preparing to travel abroad for surgery.
The traffickers offered up to $100,000 (£65,700) per kidney but in at least two cases didn't pay the donors after the organs were surgically removed, according to police.
Israeli police spokesman Micky Rosenfeld said that the number of actual transplants was not known.
Mr Rosenfeld added that "dozens" of potential donors answered newspaper ads placed by the ring.
The donors were flown to Europe, south America or south-east Asia, where the organs were extracted.
They often returned home empty-handed and with medical complications, police said.
Israeli law bans organ sales.
One of the arrested suspects is a retired Israeli army general.
Further arrests were expected following a months-long undercover investigation across the whole country.
Police notified several potential donors shortly before surgery, as well as several people who had already travelled abroad and others who were stopped at Ben Gurion airport in Tel Aviv, Mr Rosenfeld said.
He reported that the six suspects were arrested "at different times based on where it was most convenient and most necessary."
In an unrelated case last year, an FBI sting in New Jersey exposed an organ trafficking ring that operated for more than a decade.
US citizen Levy Izhak Rosenbaum was charged with conspiring to arrange the sale of an Israeli citizen's kidney for $160,000 (£105,000).