King County prosecutors have charged a 42-year-old man with killing his 69-year-old mother by stabbing her.

The prosecutor's office filed the firs-degree murder charges on Friday against Brodie Lamb.

Authorities say Lamb was frustrated his mother Margaret Ryan would not let him into her apartment, so kicked in her door and grabbed a kitchen knife. He stabbed his mother 18 times, including through the throat.

Lamb then called 911 and informed the dispatcher he had just killed his mother.

A $2 million bail was set for Lamb, who remains in custody. He's due back in court November 29 for arraignment.