BRUNSWICK, Ga. -- One day after Demarquise Elkins' mother, Karimah, watched her son stand before a judge, she and her sister have found themselves on the wrong side of the law.
Officer Todd Rhodes with the Brunswick Police Department said, "They were both arrested last night for giving false statements to police."
Up until this point, Demarquise's aunt Katrina had been his alibi, telling the media that her nephew was with her the morning of the shooting. While investigators won't confirm that's the lie she told, they do say something the sisters said while in custody led them to witnesses, which led them to a key piece of evidence.
"At 8 a.m., we found the gun," said Glynn County Police Chief Matt Doering.
Using an underwater metal detector, investigators say they found a handgun in a saltwater pond off Highway 17.
"The weapon has been sent to a crime lab for analysis to determine whether or not that is in fact the murder weapon," said Officer Rhodes.
Sherry West says Elkins and 15-year-old Dominique Lang shot her and her 13-month-old boy last week in a botched robbery attempt. Antonio Santiago didn't survive.
Right now, the teenagers are in jail, as investigators continue to search for clues.
"We're not going to rest until all the facts are in," said Rhodes.
Elkins is due in court April 5th. He and Lang are each charged with first-degree murder.