Barcelona observed a "standstill" on Monday to condemn the violent scenes that marred Sunday's independence referendum in Catalonia.

Hundreds of people are said to have been injured following clashes between police and people attempting to vote on whether the region should secede from Spain, with the country's central government having declared the referendum illegal.

Catalonia's Democracy Board, a regional body created to defend the rights of citizens, issued a call for businesses to stop their operations at 12.00 local time on Monday in a show of protest against the violence.

Barca employees across the club's offices took part, with a statement later confirming: "FC Barcelona heeded the call by the Taula per la Democracia (Democracy Board) and came to a standstill this Monday morning from 12.00pm to 12.15pm CET to vehemently condemn the use of violence to prevent the exercise of free democratic rights and the freedom of expression of its people during the referendum that took place throughout Catalonia this Sunday.

"By their own free will, the club's employees all stopped what they were doing and left their workplaces for a quarter of an hour. The same thing happened right across the FC Barcelona premises: in the club offices at Camp Nou, at La Masia, and also in the Miniestadi and Ciutat Esportiva."

President Josep Maria Bartomeu had earlier said the police clashes had "saddened" everyone associated with the club, while defender Gerard Pique described playing in a match against Las Palmas on Sunday as the worst experience of his career.

The LaLiga game at Camp Nou was played behind closed doors, with Bartomeu stating Barca had been told by the Liga de Futbol Profesional (LFP) they would be docked six points if they refused to play.

He said the decision to play without fans in attendance was made to show their disagreement with the LFP's stance, although vice-president Carles Villarubi is said to have resigned in protest, insisting the match should not have gone ahead.

Preliminary results of Sunday's poll showed a 90 per cent vote in favour of independence.