Tokyo (CNN) -- Japanese authorities are holding an American man on suspicion of killing a female Irish exchange student in Tokyo, a police spokesman said Friday. Police charged a second American man with groping the dead woman's friend. Nicola Furlong, 21, died in a hotel room in the presence of one of the men last month, according to the Tokyo Metropolitan Police. The 19-year-old man, whom police declined to identify because he's considered a minor under Japanese law, was arrested on suspicion of murder, a spokesman for the Tokyo police said Friday. The man, a musician, had been previously detained on suspicion of improperly touching Furlong's friend, but was not charged with that offense. The police have 20 days to decide whether to charge him with murder.
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Police decline to name the 19-year-old murder suspect because of his age
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Nicola Furlong, an Irish exchange student, was found dead in a Tokyo hotel
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A second American, James Blackston, is charged with groping the dead woman's friend
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Blackston's lawyer says his client is not guilty and will fight the charges
Police: Two Americans arrested after Irish woman's death in @placeholder