CONCORD (CBS SF) – Police were searching for two armed robbery suspects who held up a drive-in theater in Concord and a convenience store in Clayton on Sunday night.

Just before 9 p.m. Sunday, a pair of robbers—one armed with a handgun—demanded cash from an employee working an outdoor ticket booth at the West Wind Solano 2 Drive-In Theater in Concord, Lt. Steve Dyer said Monday.

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Less than half an hour later, police responded to a report of an armed robbery at a Shop-N-Go store in the 5400 block of Clayton Road in Clayton.

In both cases, at least one of the robbers wore a skeleton mask and both wore black hoodies, authorities said.

In the first robbery, the pair ran up behind the cashier at the drive-in theater and demanded money as one robber brandished the handgun, Dyer said.

The cashier handed over the money and the suspects ran away along Olivera Road, the lieutenant said.

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Shortly after 9:15 p.m., two suspects—both armed with semi-automatic weapons this time—showed up at the Clayton Shop-N-Go store and demanded money from the register, Sgt. Tim Marchut said.

They also took a wallet and cellphone from an exiting customer whom they had forced to return to the store and lie on the ground, Marchut said.

Police are reviewing grainy surveillance footage of the convenience store robbery, Marchut said.

Dyer said it is too early to tell whether Sunday night’s robberies are linked to a string of armed robberies that occurred throughout Contra Costa County over the past two months, but noted that police arrested three suspects in the previous crimes after a Concord 7-Eleven was robbed on Thursday.

The three suspects in custody are all teenage boys from Antioch—one 16-year-old and two 17-year-olds. They were being held in juvenile hall, he said.

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