Police are looking for an armed robbery suspect still on the loose, despite an attempt by a good Samaritan to catch him.

Investigators released surveillance video of the suspect being chased down Melrose Avenue last Friday. 

They say the man went into the Black Era clothing store wearing a mask, whipped out a gun and demanded cash. The victim handed over $100, but then was able to steal his gun when the security alarm went off. 

Cops say the suspect then removed his mask and fled the store, which is when a passerby unsuccessfully tried to stop him. 

If you have information, call Crime Stoppers at 1-800-577-TIPS.