A man accused of concealing the death of a Johns Creek teenager whose body was discovered at a swimming pool this summer has been convicted of stealing money from a man with special needs in an unrelated case, authorities said.

Elijah Foster was arrested in May in connection with the death of 17-year-old Mercedes Chico-Sims. The teen’s body was found at a swimming pool in a Roswell apartment complex, about a half-mile from her home.

Foster is charged with concealing the high school student’s death, but police have not said what happened.

According to the Fulton County Medical Examiner’s Office, Sims’ death was ruled a homicide by drowning that resulted from “a physical interaction with another individual.”

RELATED: Bond denied for 18-year-old accused of concealing Johns Creek teen's death

Late last month, Foster pleaded guilty to theft by deception for stealing money from a man with special needs that he met at Gwinnett Technical College, Channel 2 Action News reported.

He was sentenced to one year in jail and another four on probation, Fulton County court records show.

The victim’s father, who asked not to be identified, told the news station that Foster befriended his son on the college campus and the two began hanging out.

“I guess he just went up to my son and started talking about sports and different things,” the man said.

But not long after that, Foster scammed his new “friend” out of nearly $3,000, the man said.

“First, he was asking to borrow some small amounts of money and then he manipulated my son into thinking he was speaking with another friend of his who was a single mother and kind of exploited that,” the man said.

When he confronted Foster about his son’s missing money and tried to get it back, Foster argued that the cash was rightfully his, he said. That’s when he went to police and pressed charges against Foster for fraud.

"We're just thankful it wasn't a lot worse than it was dealing with a character like Eli," he said.

Foster remains in the Fulton County Jail without bond as he awaits his trial in the Sims case, Channel 2 reported.

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