A Nyssa man was shot and killed by police Sunday afternoon in Ontario. (The Enterprise/File)

ONTARIO – Police shot and killed a Nyssa man who was holding a California woman hostage at a home in the southeast part of Ontario on Sunday afternoon.

Dave Goldthorpe, Malheur County District attorney, said in a press release Monday that Henry Martinez Jr., 49, was shot and died after he threatened police with a knife at a house at 580 S.E. 13th St.

Goldthorpe said two deputies from the Malheur County Sheriff's Office “discharged their weapons.”

Martinez was shot “several times” according to the press release.

After Martinez was shot, police discovered the body of his girlfriend, Carlen Mercado, 51, inside the home. The release said she had been dead for some time.

Goldthorpe said Martinez and Mercado were in a relationship.

The Oregon State Police are leading the investigation into the officer-involved shooting.

The incident began at about 12:20 p.m. when the Malheur County Dispatch Center received a call from a family member of Mercado. The caller told dispatchers Mercado was being held against her will.

Officers from the Ontario Police Department and the Malheur County Sheriff’s Office responded to the home where a “hostage situation developed,” according to the press release.

Police negotiators tried to “establish contact with Ms. Mercado to ensure she was alive.”

After several hours of failed negotiations, the Malheur County SERT team deployed a flash bang grenade and gas to influence Martinez to leave the house.

This story will be updated.

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