Eleven people were found slain in a town on the outskirts of San Salvador, including eight workers at an electric plant, police said on Thursday.
Police investigating the massacre at the electric facility outside El Salvador's capital found the bodies of three other people at a nearby sugar plantation, according to authorities.
Officials said they suspect local gangs were responsible for both instances of deadly violence.
"We can't rule out the possibility that the same criminal gang is responsible for both" local police chief Howard Cotto said.
El Salvador, one of the world's most violent countries, saw a staggering 67 percent increase in its murder rate last year compared to 2014.