Attribute to lock Portal UME user

Hi SAP Expert,

Does anyone know the attribute for locking UME user id in Portal Batch Import?

I am trying to use 'Portal batch import' to mass lock portal users, that is by importing a batch file with corresponding uid. I search up and down and couldn't find the attribute that responsible for the lock status in portal.

Have anyone experience a similar issue and know where to look for the lock attribute label?

Thanks in advance.