STOCKTON (CBS13) -- Investigators are hunting at least two suspects after an armed robbery left a store owner shot repeatedly in the back.

The San Joaquin County Sheriff's Department said witnesses reported hearing multiple gunshots at the EZ Market on the 2500 block of East Waterloo Road just after noon on Sunday.

When deputies arrived, they found the 51-year-old business owner suffering from multiple gunshot wounds. The woman, who has not been identified, was rushed to the hospital for treatment.

Based on witness accounts and surveillance footage, authorities said two suspects wearing masks and dark clothing entered the store and confronted the store owner, who was behind the counter.

The first suspect -- described as 5'7" to 5'9", wearing a skeleton mask and brandishing a long-barreled revolver -- hopped over the counter while aiming the gun at the victim. A second suspect -- described as a possible female, 5'0 to 5'2" tall, wearing a dark ski mask and carrying a sawed-off shotgun -- entered the store moments later.

Something happened out of the view of the surveillance camera, and the victim was seen falling in front of the register, authorities said. The suspects cleaned out the cash register and fled in a newer model, light brown or tan minivan.

The victim suffered five gunshots to the back, according to medical personnel. Her condition is not known.

Anyone with information on the suspects is asked to contact the San Joaquin County Sheriff's Office by calling at (209) 468-4400 or anonymously texting the information to 274637 with "SJSO" at the beginning of the message.