HOUSTON, Texas (KTRK) -- One person could be connected to as many as eight robberies across Houston, according to officials.He was caught on video robbing a Walgreens on South Post Oak in March and later seen violently robbing a Cricket store two blocks away two months later.A woman who works at a local Subway restaurant was present during two of his robberies."I say to them, 'I'll be with you in a moment' and one of them say, 'You're going to be with me now. Open the drawer," she recalled.Three months later, he returned with two others."One jumped over and hit me in the head with the gun and shoved the lady down that was pregnant [and took] her purse. I opened the drawer, they took all the money, and they were gone," she said.Jeff McShan with Crime Stoppers believes the suspect could be responsible for eight different robberies."He seems to be escalating every time he goes into a different place," McShan said.In each of the robberies, he wears a similar black hoodie. In more than one, he has the number 94 on the back."He just looks like he's a pro at it. Very cocky. Looks very young. We think he might be in his late teens to early 20s," added McShan.If you have any information about this incident, call Houston police.