An NYPD officer has been indicted on manslaughter charges in the shooting death of an unarmed 18-year-old in his Bronx home in February, NBC 4 New York has learned.

Sources familiar with the case tell NBC 4 New York that Officer Richard Haste is being charged with first-degree manslaughter. He is expected to turn himself in on Wednesday.

Security video shows Graham entering his home, and police running after him. Police at the time said officers witnessed a drug deal and pursued Graham, believing he had a gun.

They went in and found him in the second-floor bathroom, and ended up shooting him in the chest. He died shortly afterward.

Police said later that Graham was not found with a gun.

The officers involved were stripped of their guns and assigned to desk duty.

Darnett Richards, a spokeswoman for the Graham family, said the young man's relatives were encouraged by the news but consider it a long road.

"We're happy and still, the fight isn't over, it's just started," Richards said.

Attorney information for Haste was not immediately available. The Patrolmen's Benevolent Association said in a statement that it believed the officer would be exonerated.

"We look forward to a complete review of the facts in this case which will demonstrate that this police officer believed that he was pursuing an armed felon who bolted rather than be caught with an illegal gun," PBA President Patrick Lynch said.

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