The attack happened shortly after 11 a.m. Saturday at Liberty Deli on 9th Ave just north of 48th Street in Hell's Kitchen.
Police believe a homeless man walked into the store and slashed the worker without warning. Rigoberto Reyes, 57, was caught a short while later.
The deli worker, who did not have a second to respond, had to get stitches in his shoulder.
The deli owner tells Eyewitness News that Reyes is known to them - they claim they usually have to ask him to refrain from drinking outside their door, but had not seen him for about a month.
The 30-year-old worker is recovering at home, while business at the deli goes on as usual.
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