SACRAMENTO (AP) — Two Mexican nationals charged in the slaying of a Northern California sheriff’s deputy are in the country illegally, authorities said Thursday.

The two suspects had been tending an illegal marijuana garden during the shooting last month, U.S. Attorney McGregor Scott said.

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Scott announced indictments involving four men, including the owner of the property where El Dorado County Sheriff’s Deputy Brian Ishmael was killed.

el dorado county deputy brian ishmael

El Dorado County Sheriff’s Deputy Brian Ishmael

Defense attorneys for the four men did not return telephone messages.

Officials say property owner Christopher Ross, 47, called deputies to say someone was stealing plants from his pot garden in the Sierra Nevada foothills east of Sacramento.

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They say he didn’t reveal to dispatchers or Ishmael that he was in business with the other suspects.

Prosecutors allege that Juan Carlos Vasquez Orozco, 20, shot Ishmael on Oct. 23 when the deputy ordered everyone to come out of the garden.

Authorities say Vasquez Orozco and co-defendant Ramiro Bravo Morales are in the U.S. illegally.

Bravo Morales is charged as an accessory in El Dorado County. Both men also face federal charges of possessing firearms while they were in the country illegally.

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Vasquez Orozco and Ross have pleaded not guilty to murder charges. They also face federal counts.