A man investigators say was found holding a knife and hammer shortly after his mother was found stabbed to death and his sister was critically wounded in the same attack has been formally charged with first-degree murder.

Adrian Ramirez, 23, is also charged with attempted first-degree murder and assault, according to a news release from the 17th Judicial District Attorney’s Office.

The attack happened on Oct. 7 at a home at 7730 Lowell Boulevard, according to prosecutors.

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Adrian’s mother Cherie Ramirez, 41, was found unconscious on the floor of the home with a severe head injury. She died at the hospital. His sister, Anecia Ramirez, 24, was also injured and bleeding, according to the DA’s Office.

Prosecutors did not shed light on a motive for the crime.

Adrian Ramirez is set to appear in court for a formal advisement on Friday. A preliminary hearing is slated for Dec. 1.