Police are investigating whether a robbery using a knife at the Broadway Plaza parking garage in Walnut Creek on Wednesday is related to an incident at Stoneridge Shopping Center last Friday when two teenage girls tried to grab a woman's purse and shopping bag.

Around 5:20 p.m. Wednesday in Walnut Creek, two women reported the armed robbery that took place in a parking structure near Macy's, police said.

Two suspects approached the two female victims in their parked car and stole their purses at knifepoint, according to police. One of the victims was punched in the face before having a razor knife brandished at her throat, Acting Sgt. David Rangel said.

Police said the suspects then ran from the parking structure through the upper level of Macy's and possibly fled the shopping center in a black Lexus RX 300 SUV.

Both suspects were described as black women, about 22 years old, approximately 5 feet 6 inches tall with thin builds.

One of the suspects was described as having tattooed arms and curly dark hair and was wearing a denim jumpsuit. The other suspect was wearing a long, brightly colored tribal dress, police said.

In the incident July 6 in Pleasanton, a woman successfully fought off two teen girls who tried to grab her purse and a bag of items she was returning to Stoneridge Shopping Center at 2:57 p.m., according to a Pleasanton police report.

The woman had just arrived at the mall, and as she opened her trunk to get the items for return, two young women jumped her. One tried to grab her purse, while the other made a grab for the bag.

The victim began screaming for help, and the suspect who grabbed the purse hit her four or five times on the left side of her face. The woman managed to hold on to her belongings.

The police report said the two suspects escaped in a white Honda with two others inside. Both suspects were described as 15 to 16 years old, black with black hair, about 5 feet tall and weighing about 110 pounds. Police are checking surveillance videos for details.

Anyone with information about the robberies is asked to call Walnut Creek police Detective Leonard or Officer Keeler at 943-5844.

Bay City News Service contributed to this story.

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