The first incident happened on Sunday, March 6th at 9:10 p.m. at Broadway and West 140th Street in Hamilton Heights.
Police say the man went up to the 22-year-old victim inside a laundry room at the location, threw her to the ground, and pretended to have a knife, before sexually assaulting her.
The victim was taken to a local area hospital in stable condition.
Then, just an hour later, and eight blocks north, the suspect followed a 23-year-old woman into an elevator.
Police say he grabbed her from behind, threw her to the ground and punched her in the face.
When the elevator doors opened the victim struggled free and was able to get away.
She sustained minor injuries.
The suspect is described as being a white or light-skinned man, 25-30 years old, 5'8" tall, weighing 170 lbs. with blonde hair.
He was last seen wearing a gray hooded sweatshirt with a yellow shirt, blue jeans, black boots and a black knit hat.
Anyone with information in regards to this incident is asked to call Crime Stoppers at 1-800-577-TIPS (8477).
You can also submit their tips by logging onto the Crime Stoppers website at WWW.NYPDCRIMESTOPPERS.COM or by texting your tips to 274637 (CRIMES) and then entering TIP577.