CUPERTINO (KPIX 5) – Verizon wireless stores across the Bay Area have been targeted by armed thieves who have not been afraid to use force on their victims.

On Wednesday night, a group of thieves tried to rob employees at a store on Stevens Creek Boulevard in Cupertino. But the employees received a warning from Verizon and prevented the suspects from getting inside.

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Thieves were able to rob employees at the Southland Mall in Hayward on Thursday morning, just after opening. Armed thieves wearing white jumpsuits and black masks backed their car to the store, forced an empolyee to open a safe and stole 70 brand new phones.

A few days before, a store in Brentwood was also robbed and thieves used a stun gun to rob a store in Fremont.

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A source told KPIX 5 that employees fear going to work and being left alone.

KPIX 5 has reached out to Verizon, and a spokesperson said they believe thieves are stealing phones to sell them overseas. In response, the company is taking steps to make phones less desirable targets.

“On February 12, 2018, we began to lock phones coming to Verizon stores so that they can be initially activated only on Verizon,” a spokesperson said in a written statement.

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Verizon is also having their corporate investigations team looking into these robberies.