The number of crime syndicate members in Japan fell to a record-low 34,500 in 2017, down for the 13th straight year, on the back of stronger police crackdowns, national police data showed Thursday.

The figure dropped about 4,600 from a year earlier to the lowest level since comparable data became available in 1958.

(File photo of police raid on Yamaguchi-gumi headquarters in Kobe in 2011)

"Many people left the syndicates as they struggled to secure funding amid tighter police control and thoroughgoing efforts to eliminate (such groups)," said an official of the National Police Agency.

Of the total, main members stood at 16,800, while semi-regulars who are loosely allied with crime syndicates amounted to 17,700, the data showed. In 2016, the number of main members fell below 20,000 for the first time.

The main yakuza group called Yamaguchi-gumi had 4,700 main members and 5,600 semi-regulars under it, while the Kobe Yamaguchi-gumi, a splinter group, had 2,500 and 2,700, respectively. The Sumiyoshikai crime syndicate had 2,900 of each type of member.

The number of crime syndicate members and semi-regulars investigated in all crime cases by police reached 17,737 in 2017. Of that figure, those suspected of violating the stimulants control law accounted for 4,693, while those who allegedly committed bodily harm came to 2,095 and theft 1,874.