A gang of teenage girls are on the run after assaulting staff and stealing mobile phones in robberies targeting Vodafone stores.

Security vision shows the four females running through a Burwood Highway shopping centre in Melbourne’s east about 5.45pm yesterday.

Seconds later a scuffle erupts, with a defenceless worker dragged by the hair across the ground.

Detectives believe the same group targeted another Burwood Vodafone store, striking the owner as she closed the shop. Picture: Supplied (Supplied)

Security vision shows a scuffle erupt, with a defenceless worker dragged by the hair across the ground. Picture: Supplied (Supplied)

“They just kept going at her, punching her and punching her,” witness Craig Rouse said.

The offenders then entered a Vodafone store and stole a mobile phone before sprinting away.

About an hour earlier, detectives believe the same group targeted another Burwood Vodafone store, striking the owner as she closed the shop.

The 31-year-old victim, who is too afraid to be identified, was left bloody and injured after being struck to the face.

“(The offender) used the phone to hit me,” she recalled.

The thieves, who are all described as African in appearance, managed to steal four iPhones before a customer intervened.

The offenders entered a Vodafone store and stole a mobile phone before sprinting away. Picture: 9NEWS (9news)

“Luckily (the customer) was there, otherwise I don’t know what would have happened,” the victim said.

9NEWS has been told there have been at least a dozen thefts at dealer-owned stores over the past month.

Vodafone described the string of incidents as “concerning” in an official statement.

“Vodafone is providing support to the owners and staff of these stores.”

Investigations are ongoing.