A 21-year-old man turned himself in to police today after allegedly breaking an acquaintance’s jaw in Kailua in October.

The victim, an 18-year-old man, told the older man "good-bye" while leaving a party about 2 a.m. Oct. 1 before the older walked up to him and punched him several times in the face, police said. The suspect then left. 

The victim went to the doctor the next day and found his lower jaw was fractured.

Police said the younger man identified the assailant in a line up. The suspect was arrested Thursday for investigation of assault and released pending investigation.