Several thousand civil guards from all over the country gathered Saturday in central Madrid to demand better working conditions, police said.

United Civil Guard Association representative Alberto Moya said as many as 18,000 guards, best known for their shiny black hats, were expected at the downtown rally. City police said about 5,000 had gathered by midday for the beginning of the protest, which was scheduled to include a march to the force's central headquarters.

The Supreme Court ruled Thursday that Spain's 80,000 civil guards could hold an official outdoor rally in favor of improved pay and working conditions.

"The Interior Ministry is committed to further improve the working conditions of the civil guard, always combining the interests of staff with maintaining public safety standards," the ministry said Saturday in a statement.

The last major civil guards protest was in October 2008, but on that occasion the guards protested in civilian clothing because the rally was unofficial.

Moya said civil guards worked more hours for less pay than their regional and national police counterparts.

Tough fiscal measures and labor reforms introduced by Prime Minister Jose Luis Rodriguez Zapatero's government _ in an effort to reverse a downturn in Spain's economy and decrease its debt and its 20 percent unemployment rate _ have led to other protests and strikes.

Trade unions have called a general strike for Sept. 29 and miners are on strike at several pits in the north of the country.

The General Workers and Workers Commission trade unions said miners would begin separate marches from four starting points in the northern province of Asturias aimed at arriving for a rally in the region's capital, Oviedo, on Tuesday.

Some 3,000 miners in Spain have not been paid since June.