A Benton County sheriff's spokesman, Lt. Chuck Jones, said he couldn't release further information without jeopardizing the investigation.
Authorities disclosed at a news conference that one of the victims was pregnant with a nearly full-term baby who did not survive, the Tri-City Herald reported.
A farmworker found the bodies of pregnant 23-year-old Abigail Torres, David Perez-Saucedo, 22, and Victoria Torres, 19, who was not related to Abigail, near a cornfield south of Finley on Saturday morning. All of them were from Pasco and had been shot to death.
Officials said the three were seen in Umatilla, Oregon, across the Columbia River from Benton County, several hours before their bodies were found. Oregon law enforcement agencies have been assisting on the case.
It remains unclear how the victims knew each other or why they were together when they were killed.
Officials have called the case "complex."
Abigail Torres had recently moved back to the area to try to make a better life for herself after spending time in Texas, family and friends said.
Friends described Abigail Torres as someone who was well-liked in the Pasco community and cared deeply for her children.
Victoria Torres lived in Pasco and attended Pasco High School. School district officials confirmed she was registered to be a student in the fall.
Perez-Saucedo, a laborer, was born in Mexico and lived in the Tri-Cities for 12 years.
Information from: Tri-City Herald, http://www.tri-cityherald.com
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8/12/2014 3:21:39 PM (GMT -7:00)