In one of the strongest signs of public frustration over controversial security bills likely to be passed by lawmakers next month, thousands of people surrounded the Diet building Sunday afternoon to protest their enactment and call for the resignation of Prime Minister Shinzo Abe.

Organized by a union of three different anti-war citizens' groups, Sunday's rally was arguably the most massive in a string of similar protests in recent months.

The organizer claimed as many as 120,000 people gathered around the Diet building, with about 200 protest rallies held nationwide.