A robbery duo swiped a woman's purse Thursday, in a brazen mugging on one of SF's toniest streets.

Police say the crime went down at 6 p.m. last night, on the 100 block of Maiden Lane, a gated alley that runs between Grant Avenue and Stockton Street that is lined with expensive shops, salons, and galleries.

According to the San Francisco Police Department, the 21-year-old female victim was walking in the alley when a woman in her 20s "grabbed her purse from behind."

The victim attempted to pursue the female purse snatcher, but found herself blocked by a second, male suspect, who "stood in front of her to keep her from going after" the thief.

The pair of miscreants then fled in an unknown direction, with the bag in hand.

According to the SFPD, the suspects remain on the loose as of Friday,and no arrests have been made in the case.