A purse snatcher followed a 73-year-old woman into the subway and punched her in the face, police said.
The man followed her into the 96th Street subway station on May 2, police said. He pushed her head into a wall, punched her face and took her bag.
The robber ran off and the bag was found discarded nearby, but $60 was missing, police said.
The woman was treated for a cut to her lip, police said.
Investigators believe the same man stole a bag from a woman sleeping on the subway the week prior.
On April 29, police said a 20-year-old woman was sleeping on a downtown F train when she woke up at the 57th Street station to find a man removing her bag from her lap.
The purse snatcher ran off and her bag was found above ground nearby, but $40 was missing, police said.
Anyone with information is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477).