Police are asking for the public's help to find the person they say broke into a 21-year-old's apartment Sunday morning.

Investigators say a 39-year-old man was heading to visit the 21-year-old in her apartment on DeKalb Avenue around 7:45 a.m.

The man was being followed by the suspect, who entered the apartment building after the 39-year-old man had opened the door.

When the suspect tried to enter the woman's apartment, the man fought back, defending the 21-year-old.

Police say the suspect had a gun on him and pistol whipped the man and demanded money and jewelry.

However, the 39-year-old continued to fight back, causing the suspect to flee in a black Mercedes Benz. Police say the suspect got away empty handed.

The 39-year-old refused medical attention, but is expected to be OK.

Police say there is no known relationship between the suspect and victims.

Anyone with information is asked to call police.