A woman and her infant, both of Eritrean origin, were found dead Wednesday in an apartment on Milrod Street in Ashkelon, Army Radio reported.
Paramedics confirmed their deaths on site.
Earlier Wednesday police found the body of an Eritrean man who had apparently committed suicide. Police alleged that the man was the woman's wife, and had killed her and the infant prior to killing himself.
The circumstances behind the double-murder and suicide are still unclear.
A police spokeswoman told The Jerusalem Post
that a cell phone was found in the pocket of the man who committed suicide. It was used to track down his brother in Jerusalem, who led officers to the home containing the bodies of the man's wife and baby boy. According to initial police suspicions, the two were stabbed to death.