The first robbery occurred at 8:56 p.m. at a Round Table Pizza restaurant in the 2900 block of Treat Boulevard, Lt. Andrew Gartner said.
Two suspects with white masks across their noses and mouths entered the restaurant and ordered the employees to the floor, Gartner said. One was armed with a shotgun and the other with a pistol.
The suspects took cash from the safe and the register and ran from the restaurant.
No customers were in the restaurant at the time, and none of the employees were injured, Gartner said.
The suspects were described as two black men, between 6 feet and 6 feet 1 inch tall, wearing gloves. One had a black hooded jacket, and the other had a gray hooded sweatshirt, Gartner said.
Then at 9:37 p.m., two masked suspects armed with a shotgun and a pistol entered a Subway sandwich shop in the 4100 block of Concord Boulevard, Gartner said.
One jumped over the counter and took cash from the register before they both fled the store. Gartner said they might have left in a dark-colored SUV that was traveling west on Concord Boulevard.
No customers were in the restaurant when the robbery occurred.
The suspects were about 6 feet tall and of average build, and they were wearing gloves Gartner said. The lone employee working behind the counter could not determine their races.
Police believe the robberies could have been committed by the same people based upon the weapons and suspect similarities, Gartner said.
Concord experienced a string of robberies at similar locations about four to six weeks ago, Gartner said.
He said it's too early to tell if those robberies might have been connected to those from Monday night.