Actress Erika Sawajiri, arrested Saturday after police found the synthetic drug MDMA at her Tokyo home, admitted she’s been using it “for some time” along with other illegal narcotics, investigative sources said Sunday.

The sources said the Metropolitan Police Department received a tip about a month ago that Sawajiri, 33, had an illicit drug different from MDMA in her possession.

Investigators suspect the actress might be a chronic user.

Sawajiri was turned over to prosecutors Sunday after spending the night at a police station in Koto Ward.

Dozens of reporters and photographers had gathered from early morning to catch a glimpse of the popular film and TV actress. But they were unable to do so as she was seated in the curtained-off backseat of a vehicle when it left the station.

Sawajiri admitted to illegal drug possession after police found 0.09 grams of MDMA at her home in Meguro Ward. “There is no mistake, that is mine,” the police quoted her as saying.

Police are also analyzing a urine sample they obtained from Sawajiri, who left home Friday night for a nightclub in the Shibuya district, the sources said.

Officers from the Metropolitan Police Department raided her place of residence when she returned Saturday morning. Her mother, who lives with the actress, was at home at the time, they said, adding Sawajiri has been cooperative since her arrest.

During their raid on the house, investigators found two white capsules containing powdery substance in her room. After MDMA was detected in one of the capsules, the police arrested Sawajiri at the MPD headquarters in Chiyoda Ward at around 1:30 p.m. Saturday.

The capsules were inside a bag, which had been placed in a box with items including fashion accessories. The box was found on a shelf near the door of the room with its lid open.

The police said they will also examine the calls and contacts on her mobile phone as part of the investigation to find out how she obtained the drug.

She has appeared in a number of films, TV dramas and commercials and has also had success as a singer. She was awarded the best newcomer award at the Japan Academy Film Prize for her role as an ethnic Korean girl living in Japan in “Pacchigi!” (“We Shall Overcome Someday”), directed by Kazuyuki Izutsu and released in January 2005.

Most recently, she had a role in “No Longer Human,” a film based on the life of Osamu Dazai, one of Japan’s most renowned novelists, which was directed by Mika Ninagawa and released this fall.

The Tokyo native was due to appear next year as the lawful wife of 16th-century warlord Oda Nobunaga in the NHK series “Kirin ga Kuru,” which roughly translates to “The Giraffe is Coming.” An NHK official said later in the day that the broadcaster will consider what action to take regarding the situation.

This year she starred in a TV adaptation of Toyoko Yamasaki’s hit novel “Shiroi Kyoto.”

Her role in the 2005 drama “1 Liter of Tears” made her famous not only in Japan but across Asia with the drama’s emotional depiction of its heroine’s physical deterioration from a rare disease.

Drug arrests are serious matters in Japan with celebrities who are caught with illegal substance frequently edited out of movies and TV shows.