Syndicates such as the Yakuza targeted by officers in Tokyo in country’s biggest ever effort to tackle gangs.

Police in Japan have launched their biggest ever campaign to try to put an end to organised crime.

The investigation includes trying to find out if the Yakuza gang, Japan’s most notorious crime syndicate, played a part in a recent massive accounting scandal at camera giant, Olympus.

If so, the 92-year-old maker of photographic and medical equipment could be de-listed from the Tokyo Stock Exchange in the coming weeks.

In Tokyo’s red-light district, where the Yakuza have long held sway, police now patrol the area, ready to shut down businesses run by what Japanese call “anti-social forces”.

Police have arresting several alleged crime bosses and exposed the role of the gangs in businesses such as construction and baseball.

Al Jazeera’s Steve Chao reports from Tokyo.