CHICAGO — An elderly woman who was beaten on a Red Line train could lose her eyesight as a result of the Thursday attack, police said.

At noon, the woman was riding a northbound Red Line train and reading on her Kindle when the man walked up to her. He then “viciously punched” the woman in an unprovoked attack, police said.

The woman’s eye was seriously wounded, and the man got off the train at Jarvis Avenue, police said.

“CPD needs assistance in unspeakable attack on a senior citizen,” said Anthony Guglielmi, a Chicago Police spokesman, in a tweet. “… A man brutally attacked a woman aboard a train to Evanston. We learned today that our victim may lose her eyesight as a result.”

The man was in his 20s, black, 5-foot-7 to 5-foot-9, 160-180 pounds and had short black hair, police said. He wore a short-sleeved blue T-shirt with “Illinois” on it, jeans, brown shoes with a white heel and a black backpack.

Anyone with information about the man and attack was asked to call police at 312-744-8266.

More photos of the man from police: