An assault charge was dismissed Monday against a 55-year-old former Oak Harbor man who has now been named as “a person of interest” in his mother’s disappearance.

Raymond Willey was due to appear in Island County Superior Court for a hearing in a second-degree assault case. He was accused of stabbing an acquaintance in the head multiple times after becoming upset with his mother last February, court documents alleged.

About six months after the alleged assault, Willey’s mother mysteriously disappeared from the North Whidbey home she shared with him. Betty Tews, 81, hasn’t been seen since June 21. She had previously obtained protection orders against Willey and had accused him of putting a gun to her head, according to documents she filed in court.

Detective Ed Wallace with the Island County Sheriff’s Office said Tuesday that Willey is considered “a person of interest” in Tews’ disappearance.

On Monday, Island County Deputy Prosecutor David Carman asked Judge Vickie Churchill to dismiss the case, citing a lack of evidence. The judge agreed.

Afterward, Carman explained that prosecutors felt that they couldn’t prove the case against Willey.

“After investigating the case and speaking to witnesses, we were not able to disprove Mr. Willey’s version of events beyond a reasonable doubt,” Carman said.

The alleged victim, Oak Harbor resident Mitchell Rowley, accepted a ride from Willey on Feb. 18. Rowley claimed that Willey pulled over while driving and spoke on a cell phone with his mother, who had recently kicked him out of her home. The phone call allegedly enraged Willey, the police reports indicate.

After the phone call, Willey suddenly turned on Rowley and started stabbing him in the head and face with a pocket knife, according to the report by Detective Tony Slowik.

Willey then drove Rowley to the Whidbey General Hospital community clinic on NE Goldie Street and dropped him off. He was transported to Whidbey General Hospital for immediate treatment. Slowik wrote that the wounds were mostly superficial, but three or four lacerations required stitches.

In contrast, Willey claimed that Rowley was already injured when he picked him up and he just brought him to the clinic for help.

Because of problems identified in the case, Carman explained that prosecutors entered into an agreement with Willey in May. Under the agreement, prosecutors committed to dismissing the case in six months if Willey abided by certain conditions that largely focused on preventing Willey from having contact with the victim.

Carman said Willey complied with the conditions, so prosecutors did as they had promised and dismissed the case. He said Willey didn’t violate the conditions and faced no consequences by failing to appear in court.

Willey’s current whereabouts are unknown. Investigators believe he may be living in California, where he was arrested on suspicion of DUI a few months ago, according to court documents.