One man was killed and five others were wounded in a shooting Monday night in Northeast Washington, the Metropolitan Police Department said.

The circumstances of the shooting, including whether the victims even knew each other, were being investigated, Police Chief Robert J. Contee III told reporters.

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The shooting occurred outside an apartment building located at 15th and F Streets Northeast, Contee said.

All the victims were adult males, Contee said, and those wounded were being treated at area hospitals.

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