Police officers and firefighters responded to a report of a person falling through the ice in a marshy area at Ocean Avenue and Shepard Avenue on Sunday afternoon.
It turned out someone had stepped through ice.
The teeanger was uninjured after stepping through the ice and sinking in the water up to one knee, said Swampscott Fire Capt. Remo Zimbaldi.
Police received the report of the incident at about 2:15 p.m.
It took place near Phillips Beach.