STOCKTON (CBS13) – A Stockton police officer and a suspect are dead after a terrifying scene that played out during a domestic violence call Tuesday morning.

Stockton Police confirm six-year veteran Officer Jimmy Inn was killed in the line of duty.

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Cell phone video captured some of the intense scene.

The man was holding his 8-year-old boy by the neck, seemingly strangling him before a mystery hero ran into the frame and tackled the suspect, freeing the boy.

Obtained by CBS13

The heroic moment was part of a tragic sequence.

The suspect, 30-year-old Lance Lowe, was later shot and killed by police. By that time, he had already allegedly shot and killed Stockton Police Officer Jimmy Inn.

Kaycie McClure lives across the street from the deadly shooting scene and ran to Officer Inn after he first went down.

“I don’t know who, but another man helped me flip him over and I tried my hardest, I was looking for holes, I was trying to get his vest off,” McClure said.

McClure said she was with him for just moments, as officers arrived.

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“And I was just begging him to hang on, hang on, hang on, ‘they’re coming,'” McClure said.

Evidence markers and a shot-out police SUV window could be seen as investigators spent the day processing the scene.

The deadly shooting started as a domestic violence call. Officer Inn was allegedly shot as he walked up to the suspect home. Stockton Police Officer Pancho Freer arrived, then shot and killed the suspect.

“It was just an awful situation but the real hero today was Officer Inn, he gave his whole entire life coming to try and help somebody else,” McClure said.

A Stockton Police officer answering a call for help.

Stockton Police say the eight-year-old boy has been medically cleared.

Stockton police say they are still trying to get a statement from the woman who left that house prior to the police arriving.

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Lowe lived at the residence, say police. Police searched the residence and say they found a handgun.