Glynn County Detention Center/AP
De'Marquise Elkins, 17, one of two teenagers arrested last Friday and accused of fatally shooting a 13-month-old baby in the face and wounding his mother during their morning stroll in Brunswick, Ga.
Investigators in Georgia have discovered a handgun submerged in a marsh, a week after a baby was shot to death in the small coastal town.
The handgun was found in a pond off a highway, 2.3 miles away from the crime scene in Brunswick, Ga., Brunswick police spokesman Todd Rhodes said Thursday. No weapon had been found up until this point.
Two teen suspects were arrested last weekend in the case, a day after 13-month-old Antonio Santiago was killed and his mother was shot in the leg.
The handgun was sent to the Georgia Bureau of Investigation's Crime Lab for analysis. Police did not provide a description of the weapon.
Also Thursday, police announced they arrested the sister of De'Marquise Elkins, the older of the two suspects in custody.
Sabrina Elkins, De'Marquis Elkins' 19-year-old sister, is the third relative of his to be held in custody in connection with the investigation. Sabrina Elkins was taken into custody on a bench warrant for tampering with evidence, police said.
On Tuesday, Elkins' mother and aunt were arrested on charges of making false statements to police and concealing facts or providing fraudulent documents in matters of government.
Elkins, 17, and his co-defendant, 15-year-old Dominique Lang, have both been charged as adults. Authorities were still unclear about a possible motive for the alleged crime; police said Thursday in a press release that they believed "it appears at this time that the incident was a random act."
The only eyewitness to the shooting was baby Antonio's mother, Sherry West. West said she was walking Antonio in his stroller when two teens came up to her demanding money. When she told them she didn't have any cash on her, the older one pointed a handgun at her, she said.
"He says, 'Well, I'm gonna kill your baby,'" West said last week. "I put my arms over my baby and he shoves me. And then he shot my baby right in the head."
Both Elkins and Lang's relatives have denied to local media that either of them could have committed the crime. West picked the alleged gunman out of a photo lineup of 24 mugshots, and insists Elkins is the killer.
Before Elkins' first court appearance on Monday, public defender Kevin Gough, who represents him, told The Associated Press, "My client is absolutely, 1,000 percent not guilty."