SAN ANTONIO – A 20-year-old San Antonio man who was already in jail facing one murder charge was implicated in another murder Tuesday.
The suspect, Charles Fields, was first arrested last year for a murder that occurred in July 2015.
Now, investigators are using DNA evidence to charge him with a second killing.
The DNA evidence was lifted from a partially smoked marijuana cigarette that was recovered from the second victim's car last August, just days after his body was found under a home. That victim was identified as 20-year-old Jonathan Hernandez.
Homicide detectives waited nine months for the test results to come back from the Bexar County Criminal Investigation Laboratory before they could re-arrest Fields.
Fields was originally arrested Aug. 13, 2015, for the murder of 23-year-old Elliot Hudson.
Homicide investigators said Hudson met Fields and two other men at a local Motel 6 on July 17 to sell pot, but police said Fields pulled out a gun and demanded the drugs without paying and shot Hudson several times.
While detectives were questioning Fields about that crime, they also asked him about another murder victim. The victim's body was found Aug. 7 in a crawl space in a home located right next door to Fields' home on Potomac Street.
According to an arrest warrant affidavit, Hernandez was found when workers went to the home to do some painting.
The workers told police they found blood inside the home and noticed a foul odor.
Police found Hernandez's decomposing body in a crawl space with a gun shot wound to his head.
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The victim's father saw the story on the news and told police he believed it was his son who he'd reported missing on on Aug. 6.
The father told police the last time he saw his son he was going to meet someone from Facebook to buy a gun. That person was later identified as Fields.
As part of their investigation, detectives searched Hernandez's car but when they returned it to the family, the relatives called police and told them they found the remains of a marijuana joint inside the car. The family told investigators it didn't belong to Hernandez because they didn't know him to smoke marijuana.
That joint was sent to the crime lab for DNA testing, and in January, the DNA results pointed to an unknown male.
Investigators got a search warrant to collect Fields DNA and on May 18, 2016, the results came back, matching the DNA recovered from the joint.
Fields is now facing two separate murder charges.
He's been held at the Bexar County Jail since his original arrest last August.
His bond is set at $100,000.