Police said the 24-year-old man awoke about 7:15 a.m. at the apartment he shares with his ex-girlfriend and found her sleeping with her co-worker, also 24.

The former boyfriend grabbed a knife and threatened to stab the other man and slashed him during a struggle over the knife.

Police were called to the apartment at 55 S. Kukui St. and arrested the former boyfriend.

Gun in backpack nets charge

A 44-year-old man was arrested in Waipahu yesterday on a firearms violation following an argument with his girlfriend.

Police said the girlfriend was aware the man kept a handgun in his backpack and that she was able to wrest the pack from him during the argument.

They said the man ran from the area after the girlfriend called 911. The girlfriend confirmed to police that there was a gun in the backpack and her boyfriend called and arranged to turn himself in to police who were still talking with the girlfriend.

The boyfriend was charged with failing to properly store a firearm.

Woman slugs ex-boyfriend with baseball bat

Police yesterday were questioning a 33-year-old Wahiawa woman about an assault on her ex-boyfriend Tuesday night.

The former boyfriend, 37, told police the woman came to his home about 8 p.m. Tuesday and attacked him with a baseball bat. Police said the man received a large cut on his head, one that required several surgical staples to close.

The ex-girlfriend left the home before officers arrived but surrendered later at the Wahiawa Police Station and was arrested on suspicion of second-degree assault.

Stolen vehicle leads to arrest

A 22-year-old homeless man was arrested in Wahiawa early yesterday morning on suspicion of driving a stolen vehicle.

Police said a patrol officer was making routine checks when he saw a suspicious vehicle parked in a high-crime area.

The officer ran a computer check on the car's license plates and learned a 53-year-old Honolulu man reported the car had been stolen from him on Friday.