Updated

Employees at seven prisons Canada's Alberta province are on strike to protest the suspension of one of their colleagues.

Alberta Justice Minister Jonathan Denis calls the strike illegal. The province is seeking a court injunction to force the workers back to their posts.

The dispute began at the Edmonton Remand Centre on Friday after a correctional worker was suspended for complaining about safety issues.

Seventy workers who arrived for the Friday afternoon shift refused to go inside, prompting officials to put the facility into lockdown and restrict prisoners to their cells.

Guy Smith, the president of the Alberta Union of Public Employees, says employees at seven detention centers have walked off the job as of Saturday.

Denis says the centers are being "securely operated through the assistance of police and management."