District of Columbia police say they have arrested a teenager in the fatal shooting of a 15-year-old last weekend on a train station platform in Washington.

Police said in a statement Tuesday that they have arrested 17-year-old Maurice Bellamy of southeast Washington and that he is being charged as an adult with second-degree murder while armed.

Police say Bellamy fatally shot 15-year-old Davonte Washington on Saturday at the Deanwood Metro station. Police Chief Cathy Lanier said at a news conference Tuesday that more details would be released later in the day when Bellamy was expected to appear in court but that in her opinion the shooting was over "nothing."

Metropolitan Police Department district commander David Taylor said previously that a conversation escalated into an argument.