BARCELONA, SPAIN - A referendum on whether Catalonia should secede from Spain is putting intense pressure on the region's police officers, who feel caught between their oath to the nation's constitution and loyalty to local leaders who have vowed to create a new European state.



Francesc Vidal, a 16-year veteran of the force known as the Mossos d'Esquadra, described the referendum planned for October 1 as a “train collision” between Spanish authorities desperate to stop what they consider an illegal vote and Catalan separatists who insist that the balloting go forward.



“We only ask that they don't put us in the middle of it,” Vidal, a leader of the USPAC police union, told The Associated Press. “We don't know how to act. We receive orders from both sides.”



The power struggle is the most serious constitutional crisis Spain has faced in nearly four decades.



Catalan leader Carles Puigdemont has pledged to declare independence within 48 hours should secessionists manage to stage the secession referendum and win it. The move would push the country into uncharted waters and set off a national political emergency.



But if police impede polling stations from opening at schools and other government buildings, it will be a victory for Spanish Prime Minister Mariano Rajoy in a long battle against the separatists.



On Saturday, Spain's Interior Ministry announced that it would begin coordinating all police efforts in the region related to the vote, including the operations of the 17,000-strong Mossos.



That was rejected by Catalonia's regional interior chief Joaquim Forn, who said the Mossos police chief has told Spanish authorities that regional leaders would not cede command of the force.



“The Mossos will never give up the exercise of the powers that are its own,” Forn said in a statement broadcast on Catalan public television.



Forn has promised that the Mossos will ensure that the referendum happens. He told Catalan newspaper El Punt-Avui: “Not only will we not stop the referendum, we will do the exact opposite: We will facilitate that the referendum takes place.”

A woman with an ''estelada'' or Catalonia independ A woman with an ''estelada'' or Catalonia independence flag places a carnation on a vehicle belonging to police officers from Mossos d'Esquadra in Barcelona, Spain, Sept. 24, 2017. A woman with an ''estelada'' or Catalonia independence flag places a carnation on a vehicle belonging to police officers from Mossos d'Esquadra in Barcelona, Spain, Sept. 24, 2017.

?The tensions are driving fault lines in Catalonia: polls suggest roughly half of its 7.5 million residents want to break century-old ties with Spain, with the rest wishing to remain a part of the larger nation. Fissures have also formed within the Mossos, which was created in the early 1980s as part of self-governance granted to the northeastern region.

Serious doubts for many Mossos started in July, when the top two regional officials in charge of the police resigned. The regional government replaced them with Forn and Pere Soler, men with spotless pro-independence credentials.



While rank-and-file officers are concerned that police leadership may not pass down orders from a Spanish judge to stop the vote, a small group of hard-core pro-independence Mossos has promised not to stop the vote under any circumstances.



‘Anything can happen’

Jordi Costa, a Mosso stationed in the town of Vilafranca and general secretary of the 3,000-member strong CAT police union, said the unprecedented situation meant “anything can happen” - but his loyalty to Spain's constitution came first.



“This is exceptional because there is a government that against all odds has declared that it will rebel against the law. I think that is an error,” Costa said. “I swore to the Spanish Constitution just like every single one of us Mossos. If something is unconstitutional, it cannot be done.”



Just last month, the Mossos were widely praised for their quick capture and killing of jihadist-inspired extremists who carried out deadly vehicle attacks in Barcelona and a nearby town. Now the same force feels trapped by the tense political climate.



“Our image will be damaged for one side or the other,” said David Miquel, a 25-year veteran of the Mossos in Barcelona and spokesman for the SPC union representing 5,000 officers. “Some who saw us as heroes for finishing off the terrorists will now see us as villains. For others, we will be heroes for having upheld the law.”

A woman protests holding a sign next to Mossos d'E A woman protests holding a sign next to Mossos d'Esquadra police officers, in Barcelona, Spain, Sept. 20, 2017. A woman protests holding a sign next to Mossos d'Esquadra police officers, in Barcelona, Spain, Sept. 20, 2017.

Last week a huge crowd of angry protesters took to Barcelona's streets after the Civil Guard, a national police force with a much smaller presence in Catalonia, carried out raids on an office of the Catalan government. The protesters trashed the Civil Guard's vehicles and scuffled with the officers, but Miquel said it took hours until the Mossos was ordered to step in and help restore order.



“My fellow Mossos tell me that they could have done more to help, but they were not ordered to,” Miquel said. “When you see people destroying the patrol cars of your fellow policeman, it's a feeling of impotence. What we want is to receive orders that are not coming. They need to give us a detailed guide on how to act. Don't leave it in our hands. Give us instructions.”



Albert Donaire is a Mosso from a small town of la Cellera de Ter, where pro-secession sentiment runs deep. He heads a group of 200 to 300 like-minded police officers called “Mossos for Independence.”



“My personal decision is not to confiscate any ballot boxes nor close any polling stations,” Donaire said. “I am not afraid that I will end up in prison for defending democracy.”



Like many separatists, Donaire justifies his disobedience of Spanish law by citing two acts passed by separatist lawmakers in Catalonia's regional parliament. Those measures called for the referendum and established a roadmap for independence if the “yes” votes prevail.



Even though those acts have been suspended by Spain's Constitutional Court, Donaire believes the laws are valid because they are protected by international law and the right of people to self-determination.



Faced with the challenge of stopping the vote in the nearly 800 municipalities, many of them tiny villages, the Interior Ministry has rushed more agents of the Civil Guard and the National Police to Catalonia.

“It's an exceptional situation, and we have to prepare for the worst-case scenario. There could be a part of the Mossos that won't respond,” said Luis Mansilla, general secretary in Catalonia of the National Police union SUP.



The extra manpower on the ground in Catalonia will be enough to quash the referendum should the Catalan police waver, said Juan Fernandez, the spokesman for the Civil Guard's AUGC union.



“We understand it must not be easy” for the Mossos, Fernandez said.