PRESTONSBURG, Ky. (AP) — A Kentucky man charged with killing three officers in an ambush while police were serving a protective order has been indicted on 20 charges.

Lance Storz, 49, was indicted by a grand jury Monday on three counts of murder of a police officer and six counts of attempted murder of an officer, according to media reports. Storz opened fire on a group of officers on June 30 at his home in Floyd County, a rural hilly county in Appalachia, according to police.

Storz was also indicted on seven counts of wanton endangerment against a police officer, three counts of assault and one count of assaulting a service animal. A police dog was also killed in the ambush.

The slaying of three officers was the deadliest for law enforcement in a single incident in Kentucky since a prison riot left three guards dead in 1923.

Storz’s wife had sought to get away from him, according to an emergency protective order, and he became irate and wouldn’t let her leave, the Lexington Herald-Leader reported.

She was able to sneak out when officers went to check on her, but when police returned with a protective order, Storz allegedly opened fire.

Storz is charged with killing Floyd County sheriff’s Deputy William Petry, Prestonsburg police Capt. Ralph Frasure and Officer Jacob Chaffins. The officers were laid to rest last week.

Officials said Storz fired on officers with a .308-caliber rifle and AR-15 assault rifles. Chaffins was hit by a shot fired from more than 200 yards (180 meters) away and died the next evening at a hospital. Storz later surrendered.

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