By Michael Pearson. Christina Zdanowicz and David Mattingly

(CNN) — Seventy seconds: That’s how long a North Carolina family says it took for things to go horribly wrong after they called police for help dealing with their mentally ill son.

Keith Vidal, 18, died Sunday. He was shot 14 minutes after the first police officer arrived at his Brunswick County, North Carolina, home and just 70 seconds after a third officer showed up, according to CNN affiliate WECT.

The three officers were all from different jurisdictions, and family members say that third officer, who came from the nearby city of Southport, turned what had been an improving situation into an unnecessarily aggressive encounter that ended in their son’s death.

“There was no reason to shoot this kid,” the teen’s stepfather, Mark Wilsey, told WECT on Monday. “They killed my son in cold blood. We called for help, and they killed my son.”

While the state Bureau of Investigation is looking into the shooting, the chief prosecutor for the state’s 13th Judicial District, which includes Brunswick County, says it’s way too early to characterize what happened.

“I think that we can certainly understand why this family is upset right now,” the Wilmington Star-News newspaper quoted District Attorney Jon David as saying. “They just lost a child, and certainly my thoughts and prayers are with them. But what they want from this office today is justice, and I intend to give them exactly that.”

CNN first learned of the shooting through an iReport sent by a family friend. The iReport has received more than 50,000 views in 24 hours.

The incident happened Sunday afternoon when the Boiling Spring Lakes, North Carolina, family called police for help with Vidal, who had schizophrenia, CNN affiliate WWAY reported, citing Wilsey.

Vidal, who was carrying a screwdriver, threatened to fight his mother, so they called police to help calm the situation, Wilsey said, according to the station. Two officers arrived and began talking with Vidal.

The situation was calm until a third officer, a detective from the nearby city of Southport, arrived, they said.

“Everything was going good,” Wilsey said, according to WWAY. “Then this fat cop from Southport walks in the room, walks around the corner, says, ‘We don’t have time for this. Tase that kid now. Let’s get him out of here.’ ”

Wilsey said Vidal tried to run but was struck with two Taser charges and fell backward. He said the first two officers to respond got on top of Vidal.

WECT attributed a slightly different accounting of events to Wilsey. In that retelling, Wilsey said officers had pinned Vidal to the ground after he had been tased and one of the officers said, “We don’t have time for this” and shot his stepson.

The family has not spoken to CNN about the incident.

Seventy seconds after the third officer arrived, WECT reported, citing police records, police radioed that they had had to shoot the teenager in self-defense.

The Southport officer has been placed on paid administrative leave in connection to the shooting, Police Chief Jerry Dove said Tuesday. Authorities have declined to say whether he was the officer who shot Vidal.

A spokeswoman for the Brunswick County Sheriff’s office said the officer the agency had sent to the scene has not been placed on leave.

Boiling Spring Lakes Police Chief Brad Shirley said the same thing Tuesday of that department’s officer, who was the first to arrive on the scene.

Neither David nor the state Bureau of Investigation returned messages seeking comment Tuesday.

CNN iReporter Anthony Owens, the family friend, said Vidal was a slight young man who was never violent despite his mental illness.

“All he wanted to do was play drums,” Owens said. “He was so awesome.”

Owens said the incident highlights the need for more understanding and awareness of mental illness.

“I was devastated by the news and am desperate to find some kind of good that could come from this horrible situation,” Owens said.

CNN’s Tina Kim contributed to this report.

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