A west Medford man faces a Measure 11 assault charge alleging he critically injured his 79-year-old neighbor with a knife.

Ryan Lynn Clark, 33, was arraigned Wednesday in Jackson County Circuit Court on a felony charge of first-degree assault alleging he stabbed Denise Stillwell, 79, Monday evening at his home. He also faces a charge of possessing methamphetamine.

Circuit Court Judge David Hoppe set Clark's bail at $500,000 Wednesday, according to court records.

Clark left his residence, at 333 W. Jackson St., with Stillwell inside, critically injured from multiple stab wounds, according to Medford police Lt. Kerry Curtis. Police and rescuers arrived on scene after Stillwell called 911 about 9:15 p.m.

The motive for the attack isn't clear, but investigators said Clark had been undergoing "some type of emotional breakdown" when he suddenly stabbed the woman. Curtis said Stillwell and Clark were neighbors and friends.

"There's still some answers that we don't have," Curtis said. "We think that drug impairment played a factor. I think it played a big role."

Clark had fled the scene by the time crews arrived Monday, but he was home the next day. A search yielded methamphetamine in Clark's bedroom, according to an affidavit filed by Medford police.

Court documents show Clark was convicted previously in California of felony drug possession in prison or jail in February 2008.

Clark also has multiple pending felony and misdemeanor charges, Jackson County court records show, including attempted second-degree arson from last year and first-degree burglary last month.

Assault in the first degree carries a mandatory minimum sentence of 90 months under Oregon's Measure 11 law.

— Reach reporter Nick Morgan at 541-776-4471 or nmorgan@mailtribune.com. Follow him on Twitter at @MTCrimeBeat.