More than 800 people were injured as riot police stormed polling stations to prevent the vote, which had not been sanctioned by the Central Government in Madrid, from taking place yesterday. 

Television footage showed heavy-handed officers attacking those who were voting in the referendum, including women and firefighters.

The national police and the Guardia Civil - a military force charged with police duties - were sent into the region in vast numbers to stop the vote.

It led to violent and distressing scenes in Catalonia.

The referendum was called by the Catalan Regional Government but was ruled illegal by the Spanish Government.

Officials from the region have since claimed 90 per cent of those who voted believed Catalonia, the capital of which is Barcelona, should be independent from Spain.

An emergency meeting to discuss the next steps towards declaring independence has reportedly been held by the Catalan Regional Government today.

A visibly emotional Nadal, himself born in the Balearic Islands, an autonomous part of Spain, was speaking about the clashes between police and residents at a press conference prior to the start of the men's tournament at the China Open in Beijing.

The Spaniard, winner of the US Open last month to claim his 16th Grand Slam title, admitted he watched the scenes "with concern and sadness".

"I want to cry when I see a country where we have known how to co-exist and be a good example to the rest of the world get to a situation like this," Nadal said.

"I think the image we have presented to the world is negative.

"It was a sad moment, my heart sank all day.

"Moreover, from here, at a distance, you experience it differently.

"I have spent many parts of my life in Catalonia, important moments, and to see society so radicalised surprises and disheartens me."

The violence in the Catalonian capital also forced FC Barcelona to play their La Liga match against Las Palmas at the Nou Camp behind closed doors.

There was confusion as to whether the match, scheduled on the same day as the referendum, despite concerns, would take place at all.

There were suggestions it could be cancelled until the club confirmed it would go ahead but in front of an empty stadium.

Barcelona went on to win the match 3-0.

FC Barcelona had been oustpoken on the issue last week, releasing a statement which condemned the actions of the Central Government after they arrested several high-ranking Catalan officials.