A Kansas man arrested for stabbing his grandmother did so because he was angry she criticized how he did laundry.

Isaiah Langkiet was taken into custody in late August after stabbing his 64-year-old grandmother, Elvera Langkiet, twice in the neck, leaving her lying in a pool of blood, as reported by KWCH.

He then contacted 911 after vacating the premises, admitting he had just “stabbed his grandmother,” according to Law&Crime. Authorities located him on the back porch of the house.

Inside, Elvera Langkiet was discovered and transported swiftly to a hospital. Though initially expected to recover, she declined further medical care after identifying her grandson as the attacker, KWCH reported. Her condition deteriorated due to a lung disease, leading to her death three days following the assault.

An autopsy determined she died from complications of the stabbing, ruling the death a homicide, Law&Crime said.

The affidavit released this week revealed that Langkiet confessed to the police that he lashed out due to his grandmother’s criticisms, striking her and then using a kitchen knife to stab her.

He further said he was “tired” of her “b******* at him,” the affidavit said.

Following his arrest, Isaiah Langkiet was initially charged with attempted second-degree murder, domestic battery, and violation of a protection order. After his grandmother’s death, these charges were updated to include intentional and premeditated first-degree murder, as stated by KAKE.