Police said a man dressed in a camoflauge hat, bandana, tan shirt and tan cargo shorts robbed at knife-point the Roadrunner Market at 527 Princeton Road around 1:30 a.m. Tuesday.
The robber ran from the store after getting money from the register, police said.
Just before 6 a.m. the second store, another Roadrunner at 2607 South Roan St., was also hit by a man wearing the same clothing.
Police said the robber in both cases appears to be the same person.
Anyone with information about these robberies or the person responsible is urged to contact the Criminal Investigation Division of the Johnson City Police Department at 423-434-6166 or by calling Crimestoppers at 423-434-6158. Anonymous tips can also be submitted by texting 423JCPD and your tip to 847411 (TIP411) or to submit via the internet by logging in at www.citizen observer.com.