Ferndale Institution in Mission has been locked down after unauthorized items and contraband were found.
Assistant warden Tanis Kinney did not identify exactly what was found, but said the minimum-security prison was placed on lockdown at about 7:45 p.m. on Thursday in order to conduct a more thorough search of the facility.
"The search is being conducted to ensure the ongoing safety and security of the institution, its staff and the inmates," Kinney said in a release.
She said the institution will re-open as soon as the search is complete and it is determined that it is safe to do so.
Regularly scheduled visits to Ferndale may be affected. Those who have previously scheduled visits are asked to contact the institution directly.
Criminal and disciplinary charges can be laid against any individuals found to be involved in illegal activities. Kinney said.