It happened Thursday night on the 7 train platform.
Police say the suspect punched 60-year-old Luzby Gallego in the back of the head before getting on a northbound 5 train.
She was taken to the hospital for treatment for a fractured left arm and a bruised head.
On Wednesday, she was back at home in her Queens apartment.
"I felt a lot of pain and I yelled and I yelled," Gallego said. "I didn't know who the person was."
Gallego works as a school crossing guard by day, and at night, she cleans two embassies.
Each morning she walks several bocks to catch the 7 train into Midtown, followed by the return trip late at night.
"She cannot work at the moment," her daughter Viviana Martinez said. "She's going to be out of work for about six weeks and she cannot do anything on her own. I have to constantly help her get dressed, cook, clean."
Gallego will spend the next few weeks recovering at home with her arm in a cast and wondering how she will overcome the fear of riding the subway once again.
"There's a lack of security," she said. "And a lot of crazy people and you don't know where they'll show up."
Police are asking for the public's help tracking down that suspect.
Call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782). You can also submit tips by visiting the CrimeStoppers website at crimestoppers.nypdonline.org or by messaging on Twitter @NYPDTips.
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