A teenager found critically wounded beside a road last week has succumbed to her injuries on Tuesday, leaving investigators now searching for a triple murderer.

Layla Silvernail, 16, was found in southeastern Marion County on Thursday night, suffering from a gunshot wound, as CrimeOnline previously reported. The following morning, deputies responded to a call about a dead 17-year-old, on the side of the road about a half mile away. He died from a gunshot wound.

And on Saturday afternoon, deputies were alerted to vehicle partially submerged in pond. When they pulled the vehicle — which was register to Silvernail — out of the water, they found another 16-year-old girl dead from a gunshot wound inside.

Marion County investigators are handling the three cases separately, although they say the cases are connected as the three teens knew one another — and were together before they died, The Ocala StarBanner reported. The victims’ families are cooperating, investigators said.

A high school in the same area of the county was put on “Code Yellow” on Tuesday after a student found a “threatening message,” the sheriff’s office said. Investigators could not validate the message, however, and there was no indication that it was connected with the murders. The sheriff’s office said it would provide extra security around Forest High School on Wednesday.

Marion County Sheriff Billy Woods said earlier Tuesday police do not believe a serial killer is involved and said that rumor of a fourth victim are untrue. He assured the community they were safe and urged anyone with information to call Crime Stoppers of Marion County at (352)368-STOP (7867) and reference 23-22 in your tip.

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{Featured image: Layla Silvernail/GoFundMe]