A woman who brought her baby to a medical office in Bolingbrook was punched by an employee and displayed a 9 mm handgun to allegedly protect herself, police said.

About 9:45 a.m. Tuesday, officers responded to a pediatrician office at 215 Remington Boulevard for a report of an armed person, Bolingbrook police officials said.

Initial reports indicted a woman was armed with a handgun inside of a medical exam room with a small child, police said.

Responding officers immediately entered the building and began negotiations with the woman, who was later identified as Helena Moore, 30, of Bolingbrook, police said.

Moore peacefully surrendered and was detained, police said.

After further investigation, officers learned Kimberly Tobias, 26, of Bolingbrook was an employee at the pediatrician office and punched Moore in the face, police said.

The incident stemmed from an altercation the two women had years ago, police said.

Moore displayed a 9 mm Sig Sauer handgun to allegedly protect herself, police said.

Moore was arrested on charges of aggravated unlawful use of a weapon and taken to the Will County jail.

Tobias was charged with battery and released on her own recognizance.