Divers search for gun connected to NYPD officer's murder

NEW YORK (WABC) -- Divers will return to the water Friday after taking a brief break overnight from the exhaustive search in the murky waters of the East River.

Officers did recover a folding knife, which they believe may have been tossed by accused cop killer Tyrone Howard. But the gun they said was used to kill New York City Police Department officer Randolph Holder Tuesday night, is still missing.

A nearby fisherman heard a splash at the time of the shooting, and that was believed to be the gun hitting the water.

The search taking place at East 120th Street in the East River. NYPD divers constructed a painstaking search for evidence. Crime scene investigators carried away a spent round from divers who pulled it up from the bottom of the swirling currents of the East River.

The divers have been searching since the shooting Tuesday night.

"This is literally a hand over hand search at the bottom of the river. There is technology available, but the application wouldn't work here. So they literally set a grid and they have to check by hand each inch of the bottom of that bay. And they can't miss a spot. Missing a six inch square spot could be missing the gun," NYPD Deputy Commissioner Steve Davis said.

The NYPD said it is optimistic that the gun will be found.

"Based on the fact that they initially found the clip for the gun with 13 live rounds in it, so they are hoping that the gun isn't too far away. In the meantime, yesterday morning, we recovered a gun that was obviously here for a long time, they found a spent cartridge which they believe to be Officer Holder's partner's cartridge and they found two spent bullets. Just recently, they found some old Army, a clip from an old antique Army gun," Davis said.

One spent round was found early Thursday evening by the divers, and it could prove critical to the investigation.

"That spent round, we are ballisticaly going to try to match that to a gun. It's either the officer's gun, or once we find it, Mr. Howard's gun, and that's going to be a ballistic evidence search," Davis said.

It is very difficult for the divers to reach the bottom as they move quickly, and there is a slack period of just 90 minutes at a time for the divers to search.

That section of the river is being treated as a crime scene.

As the search for evidence continues, the period of mourning has only just begun. Randolph Holder's fellow officers made a pilgrimage to the scene, lit candles, and prayed.

"It's a very tough moment in this city. Everyone is in mourning; everyone is feeling the death of Officer Holder," Mayor Bill de Blasio said.