Crowds are gathering in downtown Madrid to mark the fifth anniversary of a protest movement that led to the creation of Podemos, now Spain's third most-popular political party.

The Democracy Now platform has urged people to "occupy squares in all the world's cities on Sunday" to protest austerity, corruption and a lack of transparency in government. A large demonstration planned in Spain's capital.

Madrid's Puerta del Sol square became the scene of a protest that lasted 28 days in 2011, sparking a movement that spread to other Spanish cities and similar "Occupy" sit-ins in cities across the world.

The protests by those calling themselves "Indignados," or people angered by Spain's existing political parties, led to the emergence of Podemos, which will vie for power in a June 26 election.