Police in Northern California said Saturday they have charged four people with kidnapping a 57-year-old woman more than a week ago and then holding her for ransom.

Elvira Babb, of Vallejo, vanished June 29. Vallejo police said they are continuing to look for her and need the public’s help, KTVU reported.

“The victim’s been gone for over a week, so it causes us some concern, obviously,” Vallejo Police Lt. Jeff Bassett said. “We’re hopeful we’ll be able to locate her alive.”

Police said Emmanuel Espinoza, 26, of Stockton, and the other suspects sent a text to the woman’s son, John Babb of San Francisco, the day after the disappearance.

Police said the text to the son contained a threat. “That they would hurt her if (he) contacted the police and didn’t deliver the amount of cash that was specified,” Bassett said.

The ransom demand was less than $100,000, KTVU reported.

Police said John Babb contacted police after he drove to his mother’s apartment. The house was empty and his mother’s Chihuahua was dead.

Police said they arrested on Friday Espinoza, Jalon Brown, 32, and Larry Young, 23, both of Sacramento, and Lovely Rauzol, 27, of Vallejo, in Sacramento. They were all jailed on kidnapping charges.

Cops said Espinoza knew the victim, but didn’t say how.

Two neighbors told KTVU that Espinoza was a former tenant in Babb’s apartment building.

Espinoza was refusing to cooperate, the San Francisco Chronicle reported.

The paper also reported that all the suspects have rap sheets. Rauzol has been arrested on prostitution charges; Espinoza has been arrested on drug and robbery charges.

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