PORTLAND, Ore. (KOIN) — A 39-year-old Portland man is in custody in Deschutes County after being arrested for allegedly planning “a violent attack” at the Smith Rock Craggin Classic at Smith Rock State Park.

The Smith Rock Craggin Classic, described by organizers as a “3-day grassroots climbing festival,” began Friday. But detectives with the Deschutes County Sheriff’s Office were alerted on October 16 by Portland police that a man identified as Samson Z. Garner was planning an attack during the festival.

On October 18, the American Alpine Club — the group organizing the climbing fest — was made aware of the threat by the various law enforcement agencies. They said they “worked closely with law enforcement agencies and the Oregon Parks and Recreation Department” to make sure festival attendees were safe.

Detectives kept a close eye on Garner, officials said, and when he left Portland for Deschutes County on October 19, they spotted Garner and his vehicle. A Deschutes County SWAT unit was involved and took Garner into custody around 2:20 p.m. Thursday.

A search warrant on Garner’s car found “evidence of the planned attack,” Deschutes County officials said.

“The Sheriff’s Office would like to thank the Portland Police Bureau for sharing this information about Garner, likely preventing a major incident in Deschutes County. Detectives have determined there is no continued threat as Garner is now in custody and, at this time the investigation indicates that Garner was acting alone.”

Garner was booked into the Deschutes County Jail on 4 charges: attempted murder, attempted 1st-degree assault, attempted 2nd-degree assault and unlawful use of a weapon.

The investigation continues. No further information is available at this time.