Allison Cozzi from Greenwich, Connecticut, claims she found a piece of a digit belonging to the manager of a Chopt restaurant in April.

Chopt is a chain specialising in salads that provides takeaway food in eastern and some southern states.

In a lawsuit filed against the store in Mount Kisco, New York, Ms Cozzi said she realised while eating that "she was chewing on a portion of a human finger that had been mixed in to, and made a part of, the salad".

The filing alleges the manager at the Chopt branch had accidentally severed her left index finger while chopping rocket (known as arugula in the US).

The manager was taken to hospital, but the contaminated rocket was served to customers, including Ms Cozzi, the suit added.

According to the Westchester health department, Chopt was fined $900 (£709).

Ms Cozzi alleged she suffered several injuries, including panic attacks, shock, migraines, cognitive impairment, sickness, dizziness, and neck and shoulder pain from eating the contaminated salad.

She is seeking unspecified monetary damages.

Ms Cozzi's lawyer did not wish to comment further on the lawsuit.

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Chopt has more than 70 locations across the US.

Sky News has asked the company for comment.