Fresno police have identified the suspect in a series of store robberies thanks to a tip.
They say 32-year-old Willie Murphy should be considered armed and dangerous.
Police say Murphy is also a sex offender and a gang member and is the suspect in six separate armed robberies over the past two months.
In each case, there was only a lone female clerk working at the business when he robbed them.
Investigators say Murphy's M.O. was to pose as a customer and then when he got up to the counter, he would flash a gun in his waistband and take money from the register and personal property from the clerks.
Anyone with information about his whereabouts should call Fresno Police Department.