King County prosecutors have charged an Auburn man of first-degree murder, accusing him of breaking into his ex-girlfriend’s apartment and killing her new boyfriend.

Prosecutors say Michael Fiorini, 26, broke into a Federal Way apartment on Feb. 24, intending from the start to kill Christopher Johnson, the new boyfriend of Fiorini’s ex. They say Fiorini had gotten drunk, called his ex 12 times, came over with a loaded pistol and extra ammo, and broke a sliding-glass door to get in.

Johnson, 27, died from a gunshot wound to the chest in the bedroom. Police found Fiorini hiding in some bushes near the apartment, in the 33000 block of 18th Place South.