PHILADELPHIA (CBS) – Investigators say a customer who intervened during the attempted robbery of Philadelphia store Monday was shot twice.

The shooting happened at about 5:45 p.m. at the Koh Kong grocery store located in the 2200 block of S. 7th Street in South Philadelphia.

According to investigators, an armed suspect entered the store and announced a robbery. Police say a regular customer who was inside the store tried to stop the robbery and became engaged in a struggle with the suspect.

During the struggle, police say the suspect shot the customer twice; once in the head and once in the leg. The victim was rushed to Thomas Jefferson University Hospital where he is listed in critical but stable condition.

After shooting the customer, the suspect ran out of the store without getting any cash. Investigators believe a second suspect, possibly a lookout, may have been involved in the robbery. Police are currently searching for two Asian males.

Investigators are looking at surveillance video in the area in an attempt to identify the suspects.

Anyone with information is urged to call 911.