Cops have identified a man and a woman they want to question in connection with two slayings in Brooklyn stores that have unsettled workers and business owners, sources said Monday.

The man and woman are not considered suspects at this point, but sources say they may have information about the killings, in a Bensonhurst 99-cent store Thursday and a Bay Ridge clothing shop in July.

It's not clear what their role or connection is to the shootings, if any, or why cops want to question them.

Police have spoken to least one person in connection with the murders. Detectives are interviewing anyone whose fingerprints were found in both stores, or anyone who may have been near the stores at the time, according to sources. 

Isaac Kedare, a father of four, was found dead 8:30 p.m. Thursday by customers inside his 86th Street 99-cent shop. Police now say the .22-caliber gun used in the shooting was also used to kill Bay Ridge clothing shop owner Mohamed Gebeli in July.

Both victims were of Egyptian descent, and both were shot by the same gun, NBC 4 New York has learned. In both cases, the killer or killers tried to conceal the bodies by hiding the men under clothing or mterial. 

Police are investigating whether the shooter mixed up addresses. Kedare's store number is 1877. Gebeli worked a mile away at 7718.

A regular customer at Kedare's store said the typically jovial store owner seemed bothered when she saw him just hours before the murder.

"I said, 'OK, Isaac, I'll see you some other time,'" said Annette Caldarea. "He was like, 'Oh, oh, OK, OK.' He was upset about something. I don't know what it was." 

As police search for the killer and a motive, shopkeepers are taking no chances.

"When it starts getting around dusk time, lock them," said Bonita Bravo, who works at a money transfer business just a few doors down from were Kedare was killed. 

To be safe, Bravo says customers will now have to ring a bell to be let inside the business at night.

"I'm very scared," said Mohamed Javaid, a clerk at a Bensonhurst bodega, who said he's become extra vigilant in and around his store at night.

Jacob Yzhaki, a nearby furniture store manager, said he's put a new procedure in place: no employee can open or close the store alone.

"That's what we're doing from now on," Yzhaki said. 

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