UPDATE: The two children were found safe with their father around 10:00pm in Pottsville.
Mohnton Borough Police are currently searching for 4 year old Mya Rollman, and 3 year old Nathan Rollman after they were last seen with Zachary Rollman, 29.
Zachary Rollman is reported to be driving a 2016 black Chevy Colorado pickup truck PA Reg ZNF-0964.
Police say the children are at special risk of harm or injury. If seen, call 911 immediately.