Japan's underworld, namely the "boryokudan" (gangster organizations) better known as yakuza, have been targeted with crackdowns in recent years focused on cutting their funding and expanding their criminal liability. But a new type of thug appears to be acting with impunity by operating in a legal void.

Not being card-carrying members of the yakuza or other crime syndicates, "jun boryokudan" (quasi-gangsters), are immune from the October 2011 ordinances launched to target mob funds or the December revision of the 1992 Organized Crime Group Countermeasures Law that gave police greater authority to combat organized crime.

Coined by police in March, the term jun boryokudan refers to a less-organized type of gangster that is no less a menace to society. Jun boryokudan were involved in last September's fatal beating of a bar owner by bat-wielding thugs at a club in Tokyo's Roppongi district.