Five men robbed a couple parked at Stanford Shopping Center, taking jewelry and a purse before escaping in two separate cars on Aug. 31. While stuck in traffic, one of the vehicles rammed into a pickup truck in order to flee the area, police said.

Officers responded to the parking lot near Nordstrom at 180 El Camino Real around 2:10 p.m. on a report from a loss prevention officer who believed they saw a car burglary in progress. The incident was reclassified as a strong-arm robbery after one of the victims contacted law enforcement while police made their way to the scene, according to a police press release.

The couple, a man and a woman in their 30s, returned to their car when two white vehicles stopped behind them and blocked their way out of the parking spot, police said.

Two men emerged from one of the two vehicles, a white Audi, and went up to the woman seated in the front passenger seat. One of the men aimed a black handgun at her as the other man snatched her purse. The armed man then demanded her watch and snatched it from her wrist.

Three other armed men with black handguns came out of the second vehicle, a white Dodge Challenger, and went up to the man in the driver's seat as he tried to assist the woman. The encounter turned into a physical struggle during which a member of the trio punched the man's head and took his necklace, police said. The man defended himself as the men unsuccessfully tried to take his watch, and the trio retreated to the Challenger.

The men in the Audi and Challenger followed each other out the parking lot and headed east on Sand Hill Road, where they landed in traffic east of Arboretum Drive. The man driving the Challenger honked in an effort to get other vehicles to move. When that didn't work, he drove into the rear of a black 1993 Toyota T100 pickup truck, which gave the Challenger and Audi space to drive through, police said.

The Toyota driver, a man in his 30s, didn't report any injuries. His truck sustained minor damage.

The men who robbed the woman were seen in black ski-style masks that completely covered their faces and gloves.

The man who lost his necklace was left with minor injuries to his head and neck, but turned away medical assistance at the scene, according to police. He recalled the trio all wore dark clothes and one of them was about 6 feet tall.

The robbers could face a series of felony charges, such as robbery, conspiracy and assault with a deadly weapon, which stems from running into the pickup truck to leave the area, police said.

Police have released a photo of the Challenger taken from a surveillance system, but there were no "usable" images of the Audi or the robbers available as of Aug. 31, according to the press release. Investigators are looking into whether there are any ties with the robbery and other recent crimes in the area.

Anyone with information about this incident is asked to call the department's 24-hour dispatch center at 650-329-2413. Anonymous tips may be emailed to paloalto@tipnow.org or sent by text message or voicemail to 650-383-8984.