Suspect in custody after sexually assaulting boy in Loop convenience store

CHICAGO - A teenage boy was sexually assaulted while in a convenience store in the Loop Thursday night, Chicago police say. 

Officers responded to a store in the first block of Jackson Boulevard at 9:30 p.m. and spoke with a 15-year-old boy who said a man grabbed him. 

The victim fled the scene and the offender was arrested when officers arrived. 

Police say charges are pending while detectives continue to investigate.