Another lock down is in place at Collins Bay Institution in Kingston.
Correctional Services locked down the medium security unit of the prison at about 7 p.m. Tuesday.
The move was necessary for staff to conduct an exceptional search of the cells.
Correctional Services has not said what prompted the lock down or what guards are searching for.
Regularly scheduled visits to Collins Bay could be affected.
Anyone who has planned a visit should contact the prison directly.