Dentsu offices in Japan have been raided for the second time in less than a month following the suicide of an employee due to overwork almost a year previously.

Thirty investigators raided Dentsu’s headquarters in Tokyo, as well as three other branches, on Monday 7 November, following the discovery that some employees put in more overtime hours than agreed to in a pact with the labour union.

According to reports, digital account manager Matsuri Takahashi killed herself after enduring 105 hours of overtime in less than a month in December 2015.

Japan’s labour ministry released a white paper to help people prevent this sort of tragedy, legally known as karoshi, which attributed over 100 suicides in 2015 to overwork.

On 1 November, a ‘Working Environment Reforms Commission’ was announced by Dentsu to help ensure compliance with labour laws to prevent excessive overtime hours. “We take labour standards extremely seriously and want to proactively try to remove karoshi from Dentsu’s working culture,” said the accompanying release.

Dentsu Japan is having a tough time at the moment, admitting in October to “inappropriate operations” for 111 advertisers and 633 suspicious transactions amounting to approximately JPY 230m ($2.29m).