Suspect Marcos Eduardo Iriarte-Valde (top left) and in surveillance video footage next to his vehicle and victim Todd Stewart. Photo sources: Top left – Victor Mellor For Congress, top right – Blue Lives Matter Facebook page, bottom two, Martinez Police
One day after suspect released from custody on other charges
By Martinez Police Department
On Thursday, August 6, 2026, at approximately 5:09 pm, the Martinez Police Department received multiple 9-1-1 calls regarding a subject who was reportedly stabbed on Francis Court in front of a residence.
Officers responded and upon their arrival they located a 68-year-old male, identified as Todd Stewart, on the ground with injuries consistent with being stabbed. Fire and medical responded, but the subject was declared deceased at the scene.
Detectives from the Martinez Police Department Investigations Bureau responded to the scene along with crime scene investigators from the Contra Costa County Sheriff’s Office.
The suspect fled the scene in a Cadillac SUV vehicle pictured above.
He was later apprehended and identified as 36-year-old Marcos Eduardo Iriarte-Valdez (born 4/25/1990)
According to a Facebook post by Blue Lives Matter, Iriarte-Valdez is a “criminal released the day before” Stewart was killed. “Surveillance video shows 68-year-old Todd Stewart screaming for help as he is stabbed to death on his front lawn. The attack happened while Stewart was working in his open garage.
“Iriarte-Valdez…was already on pre-trial release for residential burglaries committed in Orinda in April. On August 4 he was taken back into custody for violating the terms of his home detention. The very next day a judge ordered him released on his own recognizance and referred him back to monitoring.”
“Authorities say the ankle monitor was not placed back on him until Friday morning, after Stewart had already been killed.”
According to an Aug. 12th FOXNews report, “The Department of Homeland Security told Fox News Digital it placed an immigration detainer on Iriarte-Valdez Sept. 23, 2025. The DHS said that Valdez was from Venezuela with citizenship in Spain.” He “had a prior criminal record and was facing burglary charges stemming from at least two incidents elsewhere in Contra Costa County…when a judge…ordered him released.”
According to an Aug. 12th ABC7 Eyewitness News report, “Investigators say the video shows him wearing a tactical vest before putting on a mask.” Iriarte-Valdez “appeared in court Wednesday and pleaded not guilty to murder charges” and “now, the Department of Homeland Security [is] involved and has labeled the suspect a ‘criminal illegal alien’.”
According to the California Globe, “On August 8, 2026, ICE placed a detainer on him with the Contra Costa County Jail” and the judge “is Nichelle Holmes, a Contra Costa County Superior Court judge. Governor Gavin Newsom appointed her in March 2024.”
According to localcrimenews.com, he was also arrested on April 29, 2026, for burglary, receiving or concealing stolen property, aggravated trespass, trespassing by driving on private property and loitering, prowling, wandering upon the private property of another.
According to the Contra Costa County Sheriff’s Office, Iriarte-Valdez is listed as White and was booked on May 15th then released on his own recognizance on Aug. 5th at 7:03 PM.
Also, according to the Contra Costa County Sheriff’s Office, the six-foot, two-inch tall, 175-pound suspect is Hispanic and being held in the West Re-Entry Treatment and Housing facility in Richmond on no bail. He has another court appearance scheduled for Sept. 9th at 8:30 AM in Martinez Superior Court Dept. 5.
But according to the Contra Costa District Attorney’s Office, the case returns to court September 1st at 8:30 am before Judge Michael Nieto in Richmond to set a preliminary hearing date.
The investigation is active and anyone with information is encouraged to contact Detective Dominguez at (925) 372-3451 or at cdominguez1@cityofmartinez.org.
Allen D. Payton contributed to this report.
Leave a Reply