Some payslips show a much as 700 deducted for union affiliation leaving one with only K32 as take home money.
The workers who gathered today at Sinohydro offices vowed not to go back to work until their demands are met. Anti riot police are standing on alert.
The workers are also demanding for salary incremens and are also calling for the dismissal of the Chinese human resource manager a Mr Gao.
Pay slips also show Napsa deduction but the workers have no Napsa security numbers and have wondered how they will be able to claim their money.