Updated 03/28/14 – 10:42 a.m.

CHICAGO (CBS) — Chicago police were investigating whether overnight robberies at a pizzeria in the West Loop and a 7-Eleven in Lincoln Square were related.

CBS 2’s Courtney Gousman reports, in both cases, a man and a woman wearing scarves around their faces announced a holdup, and made off with cash.

Police have not confirmed the two robberies were connected, but said there’s a strong possibility they were committed by the same couple.

The latest heist took place at Sarpino’s Pizzeria in the 600 block of West Lake Street in the West Loop.

Around 2 a.m., a man and a woman walked in, ordered a pizza, then sat down. A short time later, they walked up to the counter, with black scarves tied around their faces, and threatened to blow up the shop.

Police said the man made reference to a duffle bag he was carrying, implying there was a bomb inside. The woman grabbed cash from the restaurant’s vault, and the two fled the scene.

A few hours earlier, there was a similar robbery at the 7-Eleven in the 2300 block of West Lawrence Avenue, in Lincoln Square.

Police said a man and a woman with scarves tied around their faces walked into the convenience store around 10:30 p.m. Thursday. The man was wielding a sawed-off shotgun. The two announced a robbery, and they took money from two cash registers, and tried to access a safe before fleeing the scene.

Manager Jeff Menier said he believes the woman was 10 to 15 years older than her male companion – possibly in her late 30s to mid 40s.

He said he wasn’t surprised when he heard they might also have robbed the Saprino’s a few hours later.

“I think they’re running a pattern, and I don’t know what motivated them, or what got them to want to do what they’re doing from that point,” he said. “It just wasn’t a clean thing to do something else like that. Just not a big surprise, no.”

The pair was caught on surveillance video, and detectives are reviewing the tapes.

Although the descriptions of the suspects in both robberies are very similar, police have not said they are connected. However, they said it’s a strong possibility they are related.

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