Officers had been called to the 300 block of Ruth Street at around 4:30 p.m. on Thursday for a report of a robbery.
A woman told the officers she had just left her home when two people approached her, threatened her with bear spray and demanded her purse, car keys and cellphone, police said in a release.
Police said members of the guns and gangs unit located the two suspects in the 1900 block of Lorne Street.
A teen boy fled during the arrest and during the foot chase, the bear spray was deployed at an officer, police said, before being arrested by another officer.
The 17-year-old boy is facing charges of robbery, assaulting a peace officer, carrying a concealed weapon and possession of a weapon for a dangerous purpose.
A teen girl who was also arrested had a knife hidden in her waistband, police said.
The 15-year-old girl is facing charges of robbery, carrying a concealed weapon and possession of a weapon for a dangerous purpose.