By Nacho Doce and Jesus Calero

BARCELONA/MADRID, Dec 1 (Reuters) - Spanish police, soldiers and park rangers are racing to identify wild boars that might be infected with African ​swine fever and prevent the disease from crossing into the country's domestic herd, which is central ‌to its multi-billion-euro pork export industry.

Operatives are using drones, infrared technology and sniffer dogs to find any boar carcasses for testing, ‌as well as sealing off the areas around animal tracks under highways and pipework to prevent live animals moving into other areas of the countryside.

Police have been stationed and have posted signs to turn visitors away since the weekend around Barcelona's Collserola mountain range, a popular attraction for walkers, cyclists and joggers from the city. Those who live inside the park ⁠were told to keep dogs on leads ‌and report any boar sightings.

On farms, trade association Interporc said strict controls already in place for disease prevention had been reinforced. These included testing and quarantining of new animals, ‍perimeter fencing and bird nets, regular disinfections and checks on drinking water, a strict employee dress code and proper storage of pig semen samples. Government vets were checking farms and taking samples, but none of the 39 in the area have tested ​positive.

'LEAVE THE WILD BOARS IN PEACE'

The outbreak has revived memories of the last swine fever outbreak in 1994,‌ when the virus reached farms, prompting mass pig culls and a complete shutdown of the country's pork exports.

Still, Emilio Garcia Muro, an agriculture ministry official, said there was no plan to launch a cull for now.

"We are going to leave the wild boars in peace, in this area," he said. "Specialized teams will be brought in ... to detect carcasses, but above all, the aim is ⁠not to disturb or kill in this type of situation."

Spain is ​the European Union's largest pork exporter and the second-largest worldwide,​ with more than €8 billion in exports annually. The sector generates over €25 billion ($29.09 billion) in revenue and employs more than 400,000 workers.

Within the EU, Spain's ‍biggest export markets are France and ⁠Italy, and outside the EU, the United Kingdom, China and Japan.

In August 2022, the Catalan authorities launched a controlled cull of spiralling wild boar populations, which had grown accustomed to venturing into ⁠urban areas and scavenging in garbage bins during the pandemic lockdowns.

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(Reporting by Nacho Doce in Barcelona, Jesus ‌Calero in Madrid, additional reporting by Joan Faus, Corina Rodriguez and Emma Pinedo, writing ‌by Aislinn Laing, Editing by Victoria Waldersee, Rod Nickel)