Police are on the alert after two incidents over the weekend involving an armed robber in the downtown Chicago area.
The first incident happened at about 9:30 a.m. Saturday in the 100 block of North State Street.
Police say a man followed a 12- and 15-year-old girl into a building, and when they got on the elevator, told them he had a weapon and demanded money.
Police say he stole an iPhone and $20. Investigators are looking at surveillance video from the incident.
The second robbery occurred at 2:30 a.m. in the 600 block of North Michigan avenue.
A 20-year-old California woman was headed back to her hotel when a man approached her from behind, placed something to her head and threatened to shoot her.
Police say he made off with her purse, which contained $60 in cash, credit cards and her cell phone.
No arrests have been made in either case, but police have suspect descriptions in both incidents.