STONY BROOK, N.Y. (CBSNewYork) – Stony Brook University Hospital reopened Wednesday morning after reports of a suspicious man wearing a tactical vest led to evacuations overnight.

University Police Chief Robert Lenahan said the situation began around 9 p.m. Tuesday.

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Officers located the man and recovered what appeared to be a B.B. gun.

They also found a backpack that had been left outside the emergency department.

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Lenahan said police searched the bag and deemed it safe, though some items were removed for additional testing.

The chief also said the man is not affiliated with the university.

The hospital and surrounding roads fully reopened about five hours later. No injuries were reported.

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Check back with CBSNewYork.com for more on this developing story.