A south Modesto teenager was arrested Saturday evening after he allegedly stabbed his mother's boyfriend because he refused to leave the family residence in the 900 block of Sonora Avenue.

The victim is expected to recover from the wounds which were inflicted at approximately 11:30 p.m.

The boyfriend showed up at the house to see his girlfriend but the son reported that she was ill and that he wasn't welcome. The teen allegedly threatened to stab the man if he didn't leave. During the attack the knife plunged into the victim's chest and arm.

The teen, whose name was withheld because of his age, was arrested on suspicion of assault with a deadly weapon.