At least five people have died from apparent drug addiction after buying a psychotropic drug online from a 55-year-old Tokyo woman, the Hyogo Prefectural Police said Thursday.

Four of the five victims are believed to have committed suicide, according to the police.

The police said five men and women, from Saitama, Wakayama and Kagoshima prefectures, died between 2010 and 2014 after purchasing drugs from Yuka Koiwai of Setagaya Ward. There are records of the five people making deposits into Koiwai's account.

Koiwai is currently on trial for allegedly violating the Narcotics Control Law by illegally selling drugs online.

Police on Thursday arrested 40-year-old pharmacist Kohei Kawahara of Nara on suspicion of illegally reselling 80 drugs, including Ravona sleeping tablets, to Koiwai for some ¥4,000 in January.

According to the police, Kawahara became acquainted with Koiwai over the Internet and illegally sold a total of 44,000 drugs for about ¥2.8 million.

Meanwhile, the Hokkaido Prefectural Police have filed criminal papers with prosecutors against a 46-year-old Sapporo woman, whose name has not been disclosed, for illegally selling psychotropic drugs to Koiwai. The woman reportedly abused the system in which people on welfare are exempted from paying medical expenses, and sold for ¥30,800 in March some 390 tablets of the Betanamin antidepressant and other drugs that she was prescribed.