Left-leaning Spanish news organisation La Tuerka claims its photographer was "assaulted and arrested by police" at a protest march in Madrid.
It uploaded this footage of the incident:
Tens of thousands of people are out on the streets of Barcelona protesting against the austerity cuts.
There are lots of families, students and union members. Plenty of firecrackers are going off but everything appears peaceful.
Footage uploaded by YouTube user CrisisEsVacuidad shows protesters clashing with riot police on Madrid's Gran Vía this morning.
Today some flights will be affected by the strikes in Europe. Please check with your airline.
Travellers have been faced with delays and cancellations today as a series of General Strikes take place across Europe. British Airways and easyJet are among the airlines forced to cancel flights from the UK.