Investigators Seek Suspect in Union County Homicide Investigation

Investigators advise Cook should be considered armed and dangerous.

42-year old Gregory Alvin Cook of La Grande Photograph Source: DMV file

(LA GRANDE, Ore.) - Investigators with the Union County Major Crimes Team have developed a suspect lead in the homicide of 51-year old Shannon Marie Sloan of Elgin.

Police say the suspect's whereabouts is unknown and investigators are asking for the public's help for information that will lead to his arrest.

A spokesman with the multi-agency homicide investigation says by Friday they had collected enough evidence and information to charge 42-year old Gregory Alvin Cook of La Grande. Cook is not in custody and investigators say they do not know where he is. Cook was last seen on foot during the early morning hours of July 31st in Hermiston, Oregon near the Wal-Mart parking lot. He is 6' 1" tall, weighs about 160 lbs., and has brown hair and brown eyes. It is not known if he still has a moustache.

He was last seen wearing white painter pants, slippers, a dark green multi-colored long sleeve shirt and white undershirt. Cook is a self-employed house painter but was not believed to working at this time. Investigators are unaware of any known associated vehicles for Cook.

Investigators believe Cook may be in the eastern Washington area. The suspect may be hitchhiking or getting rides from people unaware that he is wanted by police, or he may be using public or bus transportation.

Investigators advise Cook should be considered armed and dangerous.

Anyone with any specific information regarding the location of Gregory Alvin Cook should call the Union County Sheriff's Office at (541) 963-1017.

The Union County Major Crimes Team is comprised of detectives from the Union County Sheriff's Office, La Grande Police Department, Elgin Police Department, Oregon State Police and Union County District Attorneys Office.