TOKYO, Japan — In southern Japan, where violent gang wars continue for years, everyone has a long memory and forgiveness is rarely given. But sometimes justice is served.

This week the Japanese National Police Agency used evidence from a cold case dating back 16 years to arrest the heads of Japan’s “most violent” yakuza group—the Kudo-kai—on charges of homicide. The cops have made dismantling the Kudo-kai a police priority and want to deliver a message to the remaining 300 full-time members that resistance would be futile. Japanese authorities also have won the support of the United States in this battle. In July, the U.S. Treasury Department designated the Kudo-kai a transnational criminal organization, noting it was Japan’s “most violent yakuza syndicate,” and froze the assets of the same top executives now under arrest for murder.

On September 11, the Fukuoka Prefectural Police Organized Crime Division and the riot squad stormed the headquarters of the Kudo-kai and the home of the group’s leader, Satoru Nomura, age 67, and arrested him for his role in conspiring to murder Kunihiro Kajiwara, a leader in the local fishing industry. The Kudo-kai’s second in command, Fumio Tanoue, 58, initially escaped arrest, but turned himself in to the police on September 13.

The two bosses are accused not only of killing Kajiwara, but also of violating the firearms laws. In Japan it is illegal to own a gun. Firing one will earn you a minimum of three years in jail and possible life imprisonment. In a case like this, even though the two gangsters did not directly fire the weapon used to kill Kajiwara, they can be held responsible for the act. For years it seemed the government would never get a break in the case, which dates back to the night of February 19, 1998, in front of a nightclub when someone shot Kajiwara in the head and chest at point blank range. The police arrested two men from the Kudo-kai group in June of 2002. These low-ranking gunsels were found guilty and are now serving what amount to life sentences. At the time, the police also picked up Tanoue, but he was never indicted due to lack of evidence.Now the courts have found that the organization orchestrated the murder because Kajiwara, the head of the Wakinoura Fishery Cooperative, had rejected demands from the Kudo-kai to cut them in on public works projects. Yakuza groups in Japan often run front companies in the construction, real estate, and nuclear industries and expect a kickback or sub-contracting work in major local projects.Kajiwara’s younger brother stayed in the fishery cooperative, becoming the head of the organization. He, too, refused to work with the Kudo-kai or placate them and he, too, was shot to death just last December. In May this year, the grandson of Kunihiro Kajiwara was stabbed in the leg. In July, a woman who worked at a company run by one of Kajiwara’s relatives also was stabbed severely. The police believe that the Kudo-kai orchestrated these three attacks.In general, most of Japan’s organized crime groups try to avoid attacking civilians—some out of a code of honor, but most simply because it’s bad public relations. Japan has 21 major yakuza groups with listed offices and a very public existence. They are regulated but not outlawed; the top executives are semi-celebrities who carry business cards, and fan magazines write up their exploits. The yakuza manage to avoid being banned altogether by currying some degree of public favor, even performing humanitarian work after disasters.But the Kudo-kai has responded to the tightening of laws and efforts to ostracize it from society in recent years with blatant acts of violence against civilians. For example, they slash the faces of female bar owners who refuse to pay protection money. They are not going gently into that good night.The Kudo-kai also has engaged in a violent turf war with the Seido-kai and other rival organizations that escalated to such a frenzy of violence that the Fukuoka Police began offering rewards for people who turned in hand grenades.This December, the Kudo-kai also became the first yakuza group ever to be classified as a “Specially Designated Dangerous Organized Crime Group”—a label that allows the police to restrict its actions pre-emptively.The police have not publicly explained why they were able to reopen the Kunihiro Kajiwara case, but a source close to the investigation says a slip of the tongue by a senior Kudo-kai gang member gave the police an opening.

Japan’s statute of limitations for murder used to be 15 years—until the law was revised in 2010 to eliminate limitations on capital crimes. Under the older Japanese laws, the 1998 murder case would have been impossible to prosecute after February of this year. So in March a Kudo-kai member bragged about the murder to an organized crime detective and mentioned details of the case that only the criminals could have known. It seems the braggart was unaware of the changes in the law. The officer put the information into a report that went up the chain of command; the police decided to reopen the investigation.

Now criminal investigators all over Japan have stepped up operations to push for the dismantling of the Kudo-kai. The police have recently determined that the group has been covertly operating in the Tokyo metropolitan area as well, running sexual massage parlors and cabaret clubs, and closed in on the building they were using as a hideout. In the raids that accompanied the arrests, police also found jars filled with formaldehyde containing severed fingers. In the traditional yakuza, when men screw up badly on the job or their subordinates do, they sometimes sever a finger, usually the pinkie, and offer it up to their boss as an act of atonement.

Japan does not have a criminal conspiracy law similar to RICO, the core mafia-busting authority in the United States. Because there is no plea bargaining either, it is notoriously difficult to nab a crime boss for the murder committed by his subordinates. There is no incentive for a lower-ranking member to rat out the gang members above him, and there are a plethora of reasons—knives, garrotes, fatal “accidents”—to stay quiet.

A veteran police detective with the Osaka Police Department often likens the job of being an anti-organized crime detective to being a bonsai gardener. “We end up just trimming the branches and rarely touch the roots. We do our best to keep the tree in order. That’s what our job seems to be.”In fact, the only way victims of an organized crime attack or the family members of the deceased can really get justice is to sue the head of the yakuza organization for damages in civil court. The Japanese judges have established that yakuza bosses have “employer liability” for the actions of their subordinates.In 2012, the family of a real estate developer who had been stabbed to death by members of the Goto-gumi sued the former crime boss, Tadamasa Goto, for what was the equivalent of $2 million. Goto settled out of court for a reported $1.4 million and apologized to the family. Goto was never arrested or charged for murder. The Tokyo Metropolitan Police spent five years working the case, but the prosecution was reluctant to go forward after the only gangster who allegedly was given direct orders to make the hit was gunned down in Thailand in April of 2011. The police, knowing that the Tokyo Prosecutor’s Office was not on board, reportedly closed the case.In Goto’s case, the Japanese proverb, “The dead have no mouths,” worked in his favor. In the case of Kudo-kai case boss Nomura, the appropriate Japanese proverb appears to be: “The mouth is the gate of misfortune.” If some thug hadn’t blathered more than he should have, Nomura probably would still be a free man.In any event, for the Kudo-kai, the police arrest of their top dog is expected to have the impact of a well-thrown hand grenade. It will stir things up, but it will not begin to demolish the group.