Four doctors are among a group of 31 suspects arrested for alleged traffic-accident scams that have cheated insurers out of HK$3 million, police say.

The Commercial Crime Bureau arrested 23 men and eight women, aged between 22 and 55, on Thursday.

Police believe the insurance fraud is run by a syndicate that orchestrated three road accidents, in which car passengers sought payouts for purported injuries.

Bureau officers acted after receiving a complaint in June of suspected fraudulent accidents that triggered insurance claims.

In a typical mode of operation, a driver rammed his car into a taxi in front. All passengers in both vehicles claimed to be injured, according to a police investigation.

They consulted designated doctors and were granted sick leave certificates ranging from 52 to 94 days, police said. They then filed insurance claims of HK$100,000 to HK$900,000 for loss of income during the period of sick leave.

Three such traffic accidents took place from 2009 to 2010, involving total claims of HK$8.68 million, of which HK$3 million had been granted. The 31 suspects, arrested for conspiracy to defraud, were: three drivers and eight passengers of taxis; three drivers and 13 passengers of private cars; and four doctors.