Police suspect alleged serial rapist Joji Obara destroyed a videotape depicting his rape of Briton Lucie Blackman as well as a shovel and the electric saw used to dismember her body, investigative sources said Saturday.

Obara was served an arrest warrant Friday on suspicion of fatally assaulting Blackman and dumping her body. He has already been indicted on charges of drugging and raping six women.

The Metropolitan Police Department believes that Obara, 48, drugged Blackman, 21, in early July and raped her in his condominium in Zushi, Kanagawa Prefecture. They believe she later died from the drugs.