Spain is among the few hot spots of strong coal demand in Europe because of its expensive gas and low hydroelectric generation options.

However, economic contraction in Europe due to eurozone debt concerns and slowed manufacturing activity in the US and China has led to cuts in government subsidies to Spain’s coal mining sector.

The strike has reportedly rallied some 8000 workers from the roughly 40 mines that remain in the Mediterranean county.

Eight workers have even shut themselves inside an underground mine in the northern town of Leon in protest against government cuts, Agence France-Presse reported.

Juan Carlos Alvarez Lievano represents miners in Spain’s Confederacion Sindical de Comisiones Obreras, one of the unions organizing the nationwide strike.

“These workers were driven to this action because of the worry, discomfort and tension that they feel. Not only are their jobs at risk, but also the future of their families,” Lievano said on the European news service Expatica.

“Such a brutal cut in one year is unaffordable. It will lead to the end of the sector because companies would go into bankruptcy.”

Further north in the county’s mining region of Asturias, riot police were called out to guard the Popular Party headquarters Thursday as coal miners attended a rally in the city of Oviedo, Reuters said.

Miners are scheduled to strike again on May 30 and 31.