Two warring yakuza groups will face stronger crackdowns after public safety commissions in six Japanese prefectures designated them Tuesday as "crime syndicates at war" in an effort to weaken them and stop their escalating battles.

The two are the country's largest yakuza gang organization, the Yamaguchi-gumi, and the Kobe Yamaguchi-gumi, which split from the former in August 2015. The designation effective Tuesday bans gatherings by five or more members of the gangs in areas where their offices and senior members' houses are located.

(Police raid the headquarters of Yamaguchi-gumi in Kobe on Oct. 30, 2019.)

The areas where such gatherings are banned include the cities of Gifu, Nagoya, Kuwana, Kyoto, Osaka, and Kobe in central and western Japan.

The designation by the safety commissions in Hyogo, Aichi and four other prefectures based on the anti-crime syndicate law also prohibits members of the two groups from using offices and stalking rival gangs. Violators can be arrested by police.

The measure needs to be renewed every three months and will be lifted only after the turf war is over.

Following the breakup, the feud between the two crime syndicates has escalated since last April.

Among a series of incidents, the head of a core group of the Kobe Yamaguchi-gumi has been arrested and indicted for attempted murder in the shooting of a mobster of the Yamaguchi-gumi group in Kobe in August 2019.

The safety commissions have decided to beef up countermeasures after conducting hearings on both syndicates in December.

It is the second special designation on gang groups at war in Japan, following one issued in 2012 targeting two other yakuza groups based in Fukuoka Prefecture, southwestern Japan. The first measure was lifted in June 2014.