Kyodo did not identify the source of its information. Tokyo prosecutors declined to comment Tuesday. Toyota Motor Corp. said it had no information.
Julie Hamp, 55, who was the highest-ranking female executive at the Japanese automaker, was arrested June 18 on suspicion of bringing oxycodone, a narcotic pain killer, into Japan. The drug is tightly controlled here.
Hamp, who resigned from Toyota last week, has not been available for comment. But police say she has denied trying to import an illegal drug. Toyota Chief Executive Akio Toyoda has said he believes Hamp had no intention of breaking the law.
The drug was found by Japanese customs in a package that was sent to Hamp by mail from the U.S., police said.
Her appointment as head of communications in April had been highlighted by Toyota as a step toward promoting diversity.
Japan has among the poorest records in the industrialized world for gender equality in business and politics.
Hamp, who joined Toyota in 2012, worked in its U.S. operations until her latest promotion. Before that, she worked for PepsiCo Inc. and General Motors Co.
Hamp had been in the process of moving to Japan, the first foreign executive of Toyota to be permanently stationed in Japan. Toyoda has acknowledged the company should have done more to help her relocation.
She was arrested at a Tokyo hotel, where she had been staying while house-hunting.
Japanese media said the drugs were hidden in a package containing jewelry, and 57 pills were found. Police have refused to comment on such reports.
Police raided the automaker's headquarters in Toyota city, central Japan, as well as its Tokyo and Nagoya offices last month.
It is not unheard of for foreigners to be detained in Japan for mailing or bringing in medicine they used at home. Such drugs may be banned in Japan or require special approval. In Japan, suspects can be held in custody for up to 23 days without formal charges.
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