Gunmen opened fire on an elderly woman at Orinsunmibare market in Osogbo, capital of Osun state, on Saturday.
The victim was pronounced dead before help could get to her.
A witness said the woman was one of the labourers at a place identified as old garage, where bricklayers hire those needed for daily work at building construction sites.
The corpse of the woman was later evacuated and deposited at a hospital mortuary in the state capital.
Folasade Odoro, police public relations officer in the state, confirmed the incident and vowed that the perpetrators would be apprehended and brought to book.
