BOISE, Idaho (AP) — A southwest Idaho man who used a knife to attack a couple on a camping trip has been sentenced to 20 years in prison.

Thirty-four-year-old William Miles Buckman of Meridian received the sentence Monday in 4th District Court and must serve seven years before becoming eligible for parole.

Buckman in December pleaded guilty to two counts of aggravated battery and arson for the September attack at Swan Falls Dam that left a man and woman with cuts. They were treated and released from an area hospital.

Authorities say the attack started after the couple refused to retrieve a flashlight someone else dropped in the river.

Police say Buckman also cut the couple's tent and threatened to set it on fire.

Authorities say Buckman had been drinking alcohol before the attack.

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