A 17-year-old charged as an adult in a drive-by shooting in Danbury last month faced a judge Wednesday.

Police say Elvis Agramonte killed 18-year-old Yhameek Johnson on Father's Day.

Johnson was a recent high school graduate.

"We pray that the justice system will prosecute him to the fullest of the law and that nobody else dies in this matter," says Tina Johnson, his stepmother.

Police say social media and interviews led them to Agramonte, who had a history with Johnson.

"It appears to be some type of rivalry between two different groups. I wouldn't necessarily call them gangs but there's definitely two different groups, two different factions," says Detective Lt. Mark Williams.

"Let's start praying, we got to do better for these children, we have to," says Tina Johnson.

Flowers and candles still remain on Mill Ridge Road where Yhameek Johnson was gunned down while walking to a cookout.

"A mother and father have had their lives destroyed. There's families that are destroyed right now," says Tina Johnson.

Police say Agramonte is well-known to them with a long juvenile record. They also tell News 12 he won't be the only person charged in this case.

"We are anticipating more arrests to come in the future," says Williams.

The judge ordered Agramonte's arrest warrant temporarily sealed because of the ongoing investigation. He's being held on $1 million bond.

He's facing other charges including risk of injury, carrying a pistol without a permit and reckless endangerment.