A 25-year-old Concord man is behind bars as the suspect in a murder of a 47-year-old woman in Martinez on Saturday evening, Martinez police said.

Jason Castillo was arrested on suspicion of killing a woman in a physical fight on the steps of the Martinez Chamber of Commerce office at 603 Marina Vista Ave., police said.

The fight was reported at 7:25 p.m. between a man and woman on the steps of the closed office building, according to police.

Allegedly Castillo struck the woman and then walked away, police said.

The woman, a Martinez resident, was transported to Contra Costa Regional Medical Center in Martinez where she was pronounced dead, police said.

Officers found Castillo on Ferry Street in downtown Martinez and arrested him, according to police. He was booked into county jail on $1-million bail.

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