An inmate held in the Island County jail is accused of brutally beating another inmate over an insult, according to court documents.

Prosecutors charged Forrest K. Miller, 21, of Maple Falls in Island County Superior Court April 19 with assault in the second degree. He could face prison if convicted.

Miller was in jail, which is located in Coupeville, after he and two other men were arrested for allegedly burglarizing a marijuana store on Camano Island, according to court documents.

The alleged assault at the jail occurred on April 17.

Surveillance video showed Miller getting into a heated argument with another inmate who was standing above him on a landing.

Miller ran up the stairs and punched and kicked the other man repeatedly. He threw the man into walls, slammed his head against the wall, and punched him on the ground until the man went limp, according to a deputy’s report on the incident.

The victim was able to push an emergency button and summon corrections deputies. He suffered a large gash and swelling on his right temple as well as swelling on his left ankle.

The victim complained of a headache and had trouble talking, the deputy wrote.

Miller told the deputy that he wanted to hurt the other man because he called him an insulting word.

Miller claimed the fight was “a mutual combatant situation,” the deputy wrote.