Police arrested actor-singer Manabu Oshio on Dec. 7 on suspicion of giving the synthetic drug MDMA to a woman who died in August while they were together in a Tokyo apartment, investigative sources said.

The Metropolitan Police Department is also investigating the 31-year-old Oshio, who was given a suspended prison sentence last month for using MDMA, on suspicion of failing to take sufficient action to help Kaori Tanaka, a 30-year-old bar employee who died.

Oshio allegedly violated the Narcotics Drug Control Law by giving Tanaka the drug, commonly known as Ecstasy, at the apartment in the posh Roppongi Hills complex Aug. 2.

He was arrested after components of MDMA were found in his hair samples, the sources said.

The finding allegedly backs police suspicions that Oshio acquired the drug for himself and used it frequently.