Authorities in Catalonia are planning the biggest security operation in Clasico history for Wednesday's game between Barcelona and Real Madrid at Camp Nou.
More than 3,000 police officers and private security agents have been drafted in for the match due to concerns over demonstrations planned by Tsunami Democratic, a protest group advocating for self-determination in Catalonia.
The fixture was originally scheduled for Oct. 26 but was called off due to safety concerns following the imprisonment of nine Catalan politicians and civic leaders for their role in the region's unilateral independence referendum in 2017.
Those sentences sparked protests across Barcelona, many organised by Tsunami Democratic, and there was another one planned for the day of the game.
The match, which will draw an attendance of 100,000, was rescheduled for Dec. 18 and Tsunami Democratic subsequently called on people to convene at Camp Nou four hours before kick-off on the day of the rearranged fixture to send a message for Spain and Catalonia to "sit down and talk."
Miquel Buch, the Catalan government's Minister of the Interior, confirmed this week that the match has been classified as high risk due to the planned protests, while pointing out that the terrorism alert across Spain remains at level four (five being the highest level of threat).
"Nothing can be ruled out," he said. "There have been attacks in Europe and at Christmas fairs and you never know when a terrorist attack could be planned.
"A Barca-Madrid game could be the target of an attack. We're working with intensity so that all those attending will have their safety guaranteed."
Given the circumstances, Barcelona have made special arrangements for the game. The players will meet at the Hotel Princesa Sofia, around 600 meters from Camp Nou, at midday on Wednesday, eight hours before kick-off.
On a normal match day, the players would arrive at the stadium themselves around two hours before kick-off. They will be sharing the Princesa Sofia with Real Madrid, although both teams will be in separate sections of the hotel. The teams will share a police escort to the ground, too.
Barca are also encouraging the media to pick up their accreditation for the game the day before, where possible, and to arrive at the stadium early. They will open the doors to Camp Nou for the press at 12 p.m. CET.
Two of the major concerns are that the protests will hinder access to the stadium for the supporters and that there could be a pitch invasion.
"A pitch invasion is one of the things which worries us," Buch added. "It's something which has happened throughout history and it puts the players, the referee and those involved in the game at risk. We're working with police and the club's security to avoid this happening."
Barca's 2017 game against Las Palmas was played behind closed doors following the violence between police and civilians which marred the independence referendum. Sources have told ESPN that the main reason for not allowing fans to attend was the fear of a pitch invasion.
The 3,000 officers called in for the match trumps the 2,500 deployed for the Clasico in 2015, played at the Bernabeu, which came shortly after the terrorist attacks in Paris.
However, it's not the biggest operation for a football match in Spain. This year's Champions League final between Liverpool and Tottenham drew 4,700 security personnel in Madrid, while last year's Copa Libertadores final, also in Madrid, saw the deployment of around 3,700 officers.