Media playback is unsupported on your device Media caption WATCH: One of Flo6x8's flamenco flashmob events

Banks are big in the news - all kinds of unexpected things are taking place in them these days. But walk into one of the plush, if financially troubled, branches of Bankia or Banco Santander in Seville and you may be in for a surprise.

Flamenco is almost everywhere you look in the Andalusian capital - tourist shops sell everything from polka-dot dresses to guitar fridge magnets, while bright posters in bars promise "authentic flamenco show".

One of the last places you might expect to find it, however, is standing next to a cash machine or queuing to pay in your salary cheque.

Yet it was right here, in the city's banks, that a new and exciting movement in flamenco was born.

Flamenco flash mobs - seemingly spontaneous dance and song performances - have been taking place in banks not just in Seville, but all over Andalusia, causing short, if amusing disruptions to the working day.

Some involve just one or two dancers, performing silently in front of bemused customers and clerks. Others can be made up of several dozen bailaores clicking their fingers and stomping their feet to recorded music.

The flash mobs are staged by an anti-capitalist group known as Flo6x8 to express anger and frustration at the economic crisis.

"At first there is surprise," says Pepe El Moody's (a pseudonym), one of the organisers, describing how people in the banks tend to react to these events. "Older people stand terrified in a corner, and mostly the bank employees are sympathetic, because they are suffering in this [economic] situation."

Interestingly, the flash mobs are reconnecting flamenco with its origins as an art form of protest and social awareness.

Talk to many people involved in flamenco today and they will tell you that there is nothing political about the music.

Yet look back at the history of flamenco, and a different picture emerges. Far from concentrating on love and passion - themes that one might expect from such an explosive art form - the lyrics sung in the late 18th and early 19th Centuries were largely about poverty, suffering and the hardship of everyday life.

I can't sing about love, because I'm not in love with the situation now Juan Pinilla, Flamenco singer

As with the blues, or other subculture music genres such as Greek rebetiko, these songs were mostly performed by groups marginalised by mainstream society - in the case of flamenco, by Roma gypsies.

"The first lyrics that we have in the history [of flamenco] explain the situation of exploitation, of misery," says singer, historian and political activist Juan Pinilla.

"If you explain your situation, your misery, you are talking about politics," he adds.

Later, as flamenco was absorbed into the cafe society of the end of the 19th and beginning of the 20th Centuries, the lyrics began to change, however, and different songs were sung.

Flash mobbing around the world The first flash mob took place in the rug department of New York's Macy's department store in June 2003

Flash mobs have been performed all over the world - from Abidjan in the Ivory Coast to Hanoi in Vietnam (pictured)

Marriage proposals, pillow fights, breast-feeding protests and "No pants on the subway" days have all been performed as flash mobs Flash mobbing and its unstoppable rise

Yet a protest side to the music remained, and was to the fore in the years leading up to the Spanish Civil War.

When, in July 1936, the conflict broke out, the vast majority of flamenco performers - 95%, according to Pinilla - supported the Republican government against General Franco's military rebels.

However some, such as the singer Corruco de Algeciras, were forced to fight on Franco's side. Corruco died at the Battle of the Ebro in 1938, killed by the same people who sang his pro-Republican songs.

Once the war ended in 1939 and Franco emerged victorious, many in the world of flamenco had to keep their political beliefs to themselves for fear of reprisals.

Their lyrics were subject to censorship and government agents were often present at performances, keeping an eye out for any criticism or attacks on the regime.

Franco himself liked flamenco, however, and started using it to promote an image of a unified country to the rest of the world.

Image caption These Spanish flamenco dancers performed in London in 1951

Sanitised and depoliticised, it helped attract tourists, who were now flocking to Spain and the Costas in their hundreds of thousands.

Yet in the 1960s and 1970s a new, underground and more political version of flamenco began to emerge once again, often using metaphorical language to get its message past the censors.

The leaders of the movement were Francisco Moreno Galvan and Jose Menese.

Moreno Galvan was a painter and poet from the small town of Puebla de la Cazalla, near Seville. He discovered Menese, a young singer whose family had been persecuted under the Francoists during the civil war, and began writing lyrics for him that subtly criticised the governing regime.

Image caption Paco de Lucia, one of the world's finest flamenco guitarists, proves that not all flamenco is political

"I wanted to sing what I felt deep inside," says Menese, remembering those years, "about how much they had made me suffer."

One of his best-known songs reflected the strict social hierarchy of the times - and a burning anger against it.

You my good sir, on your horse, not bidding us good day,

If your horse were to go lame a different bird would sing.

Franco died in 1975 and Spain began moving towards democracy. Other flamenco singers, including Enrique Morente, also became increasingly political.

Yet the protest side of the art form remained little known outside Spain - Paco de Lucia and Camaron de la Isla, with their new sound, became the public face of flamenco, and they were not interested in songs of protest.

Now, however, with almost six million unemployed and many formerly affluent Spaniards having to rely on charity to stay alive, this is being reflected in flamenco - not least the Flo6x8 flash mobs.

We are planning more protests Pepe El Moody's, Flo6x8

The Spanish government is clearly rattled - after a Flo6x8 video (see top of story) got over a million hits on YouTube they changed the law to make it much more difficult for the bank flash mobs to be carried out, and none has happened over the past year.

Instead it has gone international.

Flamenco flash mobs have been taking place, not only in Spain, but across Europe, in Milan, Rome and the UK, though it has become harmless fun, rather than a political act.

Flo6x8 have vowed to continue using flamenco to get their message across, however.

"We are planning more protests," says Pepe El Moody's, refusing to give any details.

Although not part of the Flo6x8 movement himself, singer Juan Pinilla is also adamant that the lyrics of protest are the most relevant expression for flamenco in the current climate.

"I can't sing about love," he says, pointing out that no one in his family has a job at the moment, "because I'm not in love with the situation now.

"This is the history of flamenco. But flamenco artists have forgotten this.

"They have forgotten that flamenco is the music of exploited people, of an exploited country."

Jason Webster's documentary Flash Mob Flamenco was broadcast on BBC World Service and BBC Radio 4. Listen back via BBC iPlayer Radio, or browse the documentary podcast archive.

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