As part of a major sweep of a brutal Kyushu yakuza group that has resulted in 15 arrests, the Fukuoka Prefectural Police have issued fresh warrants for two top leaders of Kudo-kai who are being held in connection with a separate case involving a murder.

Satoru Nomura, the 67-year-old leader of the group based in Kitakyushu, Fukuoka Prefecture, and Fumio Tanoue, 58, second in command, were both given two additional counts of attempted murder for their alleged involvement in a January knife attack on a female nurse in Fukuoka.

Keigo Kikuchi, 42, the third-ranking leader, and executives of subgroup Tanakagumi, were under arrest as of Wednesday in connection with the assault.

The arrests came as part of a major campaign by the prefectural police to crush the group, which has attacked people who cooperated in the fight against yakuza organizations.

Police are also searching for Tetsuji Tanaka, a 46-year-old ranking member of Tanakagumi.

The 47-year-old nurse was stabbed several times on the night of Jan. 28. She sustained wounds that took three weeks to heal.

The police suspect Kudo-kai was involved in the stabbing.

According to the police, Nomura, who was being treated at the hospital where the nurse worked, took exception to how she treated him and ordered his subordinates to attack her.