Authorities confirmed on Sunday morning that a gun they recovered the .40-caliber pistol they think was used to kill an NYPD officer last week.

Officer Randolph Holder, 33, died on Tuesday after investigators said Tyrone Howard shot the 5-year police veteran in the head.

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Divers recovered an unrelated gun on Thursday that they now said had been in the river a long time.

Police closed off FDR Drive between East 96th and East 132 streets on Sunday for about two hours, reopening the major throughway at around 10:30 a.m.

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NYPD have been spotted in the area, where Howard allegedly shot Holder after the officer attempted to retrieve a stolen bicycle, since Tuesday's shooting.

Holder had reported to the scene with fellow officers after receiving a call about a shooting at the East River Housing Development in East Harlem.

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An officer with PSA 5, Holder chased the armed suspect onto the FDR Drive's pedestrian overpass when Howard reportedly shot him.

The shootout with police left Howard, 30, with a gunshot wound to his leg, which was treated before he was taken into police custody.

A wake for Holder is scheduled for Tuesday at the Community Church of the Nazarene in Far Rockaway between 9 a.m. and 6 p.m.

Family, friends, city officials and fellow officers are expected at the Wednesday funeral at 3 p.m.