That would depend on the policy of the company, i.e., how serious an offense this is projected as. Implementing BIOMETRICS systems definitely removes the problem, but it comes at a high cost and may take time to implement. For a more immediate response, actions could vary from a warning given by the Reporting Manager or BU HR on the code of conduct to more severe actions, including recording the case in the ethics and compliance department.
For repeated attempts even after a warning, the employee may be referred to a senior HR manager, and more severe action may be taken. Consider also debarring the employee from availing the perfect attendance bonus for that period. However, ensure that you have physical evidence for proof, irrespective of the nature of the disciplinary action.