By Jason Allen

VENUS, Texas (CBSDFW.COM) – Counterfeit prescription pills are suspected of killing one teenage boy, and leaving two others in serious condition, in two separate incidents in the city of Venus last week.

In each case, police said witnesses who were still conscious, told police they thought they were taking oxycodone pills.

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Police said lab tests would be needed to determine what the pills were made of and if they came from the same supply.

However, there have been many confirmed cases in North Texas in recent months police said of counterfeit pills containing fentanyl.

There was concern Monday, March 22, some of the drugs could still be circulating in the community.

Venus ISD Superintendent James Hopper had a meeting with teachers and staff Monday morning to notify them of the incidents.

He was also speaking with neighboring districts to make them aware of the issue.

“It’s clearly grabbed our attention,” said Hopper. “The welfare of our students is paramount in everything that we do, and so we take this very seriously. We have very close relationships with our students, and our teachers are invested in our students to a degree it’s very emotional with them.”

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The first incident happened early on the morning of Monday, March 15.

A 16-year-old boy from Joshua died.

Two days later police were called to another address.

Police Chief James Groom said officers were the first to arrive, and performed CPR on at least one victim.

Two teenage boys were hospitalized, but neither police or school officials had an update on their conditions Monday.

“These kids are out there buying something they think is safe,” said Chief Groom. “And at the end of the day, there’s no way to tell if they’re buying it off the street, if it’s a safe pharmaceutical, or if it’s some kind of counterfeit pill that could kill them.”

Chief Groom said his department was working closely with the Johnson County Sheriff’s Office Stop the Offender Program Special Crimes Unit on the case.

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Venus is 32 miles southwest of Dallas.