It's over recent Census results, which showed a decline in the number of Welsh speakers.
The Welsh Government say the building remains open to staff and visitors as usual.
Cymdeithas are holding a peaceful protest at one of the entrances at the Welsh Government offices in Cardiff. The main reception remains open as usual to all staff and visitors.
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Father-of-three Nick Bickerstaff, from Denbighshire, was waiting for daughter Ellen and her friend in the foyer at the end of the concert.
ITV News has obtained exclusive footage of the moment armed police raided a house believed to be linked to the Manchester suicide bomber.
The suspected Manchester Arena bomber has been identified as 22-year-old Salman Abedi by Greater Manchester Police.