A pair of similar muggings moments and a block apart have raised fears that a duo of serial robbers is on the loose in San Francisco.

According to the San Francisco Police Department, the two carbon copy crimes occurred at 11 and 11:05 p.m. Tuesday night, the first at Washington and Drumm Streets, the second a block away at Drumm and Clay.

Police say that in both cases, two males in their early twenties violently robbed victims they approached on the street.

At 11 p.m., police say, the pair forced a 26-year-old woman onto the ground, and punched her as she handed over her backpack and "personal property." The duo fled on foot west on Washington, according to the SFPD.

At 11:05, two men with a similar description approached a couple who were walking at Drumm and Clay Streets. They tried to snatch the purse of the 35-year-old female victim, "but she refused to let go," police say. The men then punched her "until she let go," according to the SFPD, relinquishing her bag, wallet, cell phone, ID, and house keys. The victim and her companion, a 35-year-old male, saw the men hop into a vehicle and speed west down Washington Street.

The victim of the first mugging was injured seriously enough that she was transported to San Francisco General Hospital for treatment of her injuries, which police say were not life-threatening. The second victim was also left with non-life-threatening injuries in the attack.

The suspects remain at large, police say, confirming that no arrests have been made in either case. As always, anyone with any information on either case (or any other crimes) is urged to call SFPD's Anonymous Tip Line at 415-575-4444 or to text a tip to Tip411 with SFPD at the beginning of the message.

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