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Authorities on Wednesday formally identified the man suspected in the double homicide of a wealthy couple who were “brutally murdered” in a “blitz attack” inside their upscale La Verne-area home the day after Christmas.

A poster displayed at a sheriff's news conference May 6, 2015, indicated a suspect was in custody in the killings of Troy and Shirley Isom. (Credit: Kareen Wynter / KTLA)
A poster displayed at a sheriff’s news conference May 6, 2015, indicated a suspect was in custody in the killings of Troy and Shirley Isom. (Credit: Kareen Wynter / KTLA)

Luke Fabela, 23, a transient, was confirmed as the suspect by a Los Angeles County Sheriff’s Department lieutenant at an afternoon news conference, a day after a law enforcement source close to the investigation told KTLA that Fabela was believed to be responsible for killing Armie “Troy” and Shirley Isom.

Fabela has been in state prison in Kern County since mid-January on an unrelated charge for which he was sentenced to 32 months, sheriff’s Lt. Dave Coleman said. He was arrested by San Bernardino police on multiple theft charges, Coleman said.

A booking photo of Fabela was not made available because authorities do not want to jeopardize the investigation, Coleman said.

Investigators have been searching for the killer of the 89-year-old husband and 74-year-old wife since the fatal attack occurred on Dec. 26 at or near the front door of their house in the 300 block of Roughrider Road, according to the department.

Both victims died after sustaining blunt-force trauma, Coleman said at the time of the killings. He added that Shirley Isom had suffered sharp-force trauma.

DNA evidence from the crime scene played a role in identifying the suspect, the lieutenant said.

The motive for the killings remains unknown, Coleman said, disputing rumors that the killer was a hired hit man. Investigators believe Fabela acted alone.

Several witnesses told KTLA they saw a man outside the Isoms’ gate following the fatal attack. Investigators believe that man to be Fabela, KTLA’s source said.

Witnesses were taken to the prison where Fabela is being held and were able to identify him in a lineup, Coleman said.

Fabela has ties to Claremont, Pomona and San Bernardino.

The case has been submitted to the District Attorney’s Office for review, Coleman said. One charges are filed, an arrest warrant will be sought and the suspect will be brought to L.A. County to face prosecution, he said.

Correction: An earlier version of this story indicated the suspect was arrested in the case. In fact, Fabela has not yet been arrested in connection with the homicides, but is already in custody.

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