Police say the suspect, shown in the photo above, followed a girl into a building in Harlem on the evening of Tuesday, June 21st.
He then continued to follow the 12-year-old into the elevator where police say he sexually assaulted her.
The suspect is described as a male between the ages of 25 to 30, 5'11" and of medium build.
He was last seen wearing a stripped golf shirt and blue jeans.
Anyone with information is asked to call Crime Stoppers at 1-800-577-TIPS (8477) or by texting their tips to 274637 (CRIMES).