WASHINGTON (CBS News) — The Pentagon’s police chief said Tuesday that a Pentagon police officer was attacked on the Metro bus platform outside the building and gunfire was exchanged in an incident that resulted in “several casualties” and prompted an hour-long lockdown of the building.

Woodrow Kusse, the Pentagon Force Protection Agency’s chief of Pentagon Police, told reporters during a press briefing the attack occurred around 10:37 a.m., and officers were alerted by a radio call that an “incident was underway.”

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The encounter, which Kusse said resulted in “several casualties,” caused the Pentagon to go into lockdown for roughly an hour because of what the Pentagon Force Protection Agency said was a “shooting event” near the building’s Metro transit center.

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