Somerville police are hoping to identify an armed robber with the public’s help.

The robber was one of four men who surrounded and robbed two women at South and Willow streets in East Somerville, between the Twin City Plaza and Cambridge’s Inman Square, at about 9:15 p.m. Monday.

He showed a firearm and, “despite encountering no resistance, pistol-whipped both victims,” police said Wednesday.

This robber is described as a Hispanic male, age 16 to 19, with dark, close-cropped hair and a thin mustache.

Anyone who can identify him or provide information on the case is asked to call Somerville Detective Paul Duffy (617) 625-1600, Ext. 7219.

This post was written from a press release.